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PubMed2000

Hemodynamic performance during maximum exercise in adult patients with the ross operation and comparison with normal controls and patients with aortic bioprostheses.

This study examines the resting and exercise hemodynamic performance of the pulmonary autografts in the aortic position as well as of the homografts used for right ventricular outflow reconstruction in patients undergoing the Ross operation. Previous studies have reported excellent resting hemodynamics in patients who underwent aortic valve replacement with a pulmonary autograft. However, there are very few studies of their hemodynamic performance during exercise. Twenty adult subjects who underwent the Ross operation and 12 normal control subjects were submitted to maximum romp bicycle exercise. The valve effective orifice areas and transvalvular gradients of both aortic (autograft) and pulmonary (homograft) valves were measured at rest and at peak of maximum exercise using Doppler echocardiography. Valve areas were indexed for body surface area. The hemodynamics of the aortic valve were very similar in Ross subjects and in control subjects at rest and during exercise. However, the indexed valve area of the pulmonary valve at rest was significantly (p < 0.001) lower in the Ross subjects (1.10 +/- 0.46 cm2/ m2) than in the control subjects (1.95 +/- 0.41 cm2/m2), resulting in higher (p = 0.004) mean gradients at rest (Ross: 9 +/- 7 mm Hg vs control: 2 +/- 1 mm Hg) and at peak exercise (Ross: 21 +/- 14 mm Hg vs control: 7 +/- 2 mm Hg). The pulmonary autograft provided excellent hemodynamics in the aortic position either at rest or during maximum exercise, whereas moderately high gradients were found during exercise across the homograft implanted in the pulmonary valve position. Future improvement of the Ross procedure should be oriented toward the search of new methods to prevent the deterioration of the homografts.

Adult↗
PubMed2000

Echocardiographic evidence of hemodynamic and clinical improvement in patients paced for heart failure.

Dilated cardiomyopathy is frequently associated with electrical conduction disturbances. Development of left bundle-branch block with discoordinated ventricular contraction pattern further contributes to impaired hemodynamic performance. Biventricular pacing has evolved as a new treatment option for patients with dilated cardiomyopathy and conduction disturbances. The "electrical" approach aims to normalize the disturbed contraction pattern, thereby improving hemodynamic function by simultaneous stimulation at different ventricular sites. Acute hemodynamic improvement with biventricular pacing has been demonstrated in patients with depressed left ventricular function and delayed intraventricular conduction. Due to the variations in optimal pacing site and atrioventricular delay, individual optimization to achieve optimal hemodynamic benefit is necessary. Echocardiography has the potential to provide hemodynamic data by Doppler techniques and combine these with geometric information about ventricular volumes, ejection fraction, and contraction patterns. This article focuses on the use of echocardiographic techniques for noninvasive optimization in cardiac pacing and presents preliminary experience from the initial trials on multisite pacing in heart failure.

Arrhythmias, Cardiac↗
PubMed2002

Usefulness of B-type natriuretic peptide levels in predicting hemodynamic perturbations after heart transplantation despite preserved left ventricular systolic function.

The aim of this prospective study was to evaluate the association of peripheral B-type natriuretic peptide (BNP) levels with clinical symptoms and central hemodynamic and echocardiographic measures in cardiac transplantation. BNP reflects ventricular wall stress and correlates with severity of heart failure. No previous investigation has comprehensively assessed the rapid bedside BNP assay for predicting hemodynamic measures of cardiac allograft function in heart transplantation. We evaluated BNP levels using a rapid point-of-care assay in 87 stable cardiac transplant recipients who had 237 consecutive measurements along with endomyocardial biopsy, right-sided cardiac catheterization, and echocardiography. Using median tendencies, 2 groups were identified: the low BNP group (n = 116, BNP <150 pg/ml) and the high BNP group (n = 121, BNP >/=150 pg/ml). The high BNP group had increased right atrial pressures, higher pulmonary artery systolic pressures, pulmonary capillary wedge pressures, and lower cardiac index. Besides hemodynamic variables, the presence of right ventricular dysfunction (p = 0.05) and significant tricuspid regurgitation (p = 0.003) were associated with higher BNP levels. Independent predictors of BNP levels on multivariate analysis included elevated pulmonary capillary wedge pressure, lower cardiac index, and symptoms of dyspnea and fatigue. This initial investigation establishes the accuracy of a point-of-care BNP assay in predicting cardiopulmonary hemodynamic aberrations despite preserved left ventricular systolic function in heart transplant recipients. Rapid bedside BNP analysis may provide a noninvasive surrogate method for the comprehensive assessment of cardiac allograft function and hemodynamics in heart transplantation.

Adult↗
PubMed1997

Acute hemodynamic effects of intravenous ibutilide in patients with or without reduced left ventricular function.

Many antiarrhythmic agents have adverse hemodynamic effects which limit their use in patients with impaired ventricular function or during tachyarrhythmias. Ibutilide is an intravenous, selective class III antiarrhythmic agent that is effective for conversion of atrial fibrillation or flutter. This multicenter, randomized, placebo-controlled, dose-ranging study evaluated the effects of intravenous ibutilide on hemodynamic parameters during invasive monitoring in 47 patients with or without reduced left ventricular ejection fraction (LVEF) > 35% or < or = 35%. Patients received either placebo or ibutilide as a 10-minute loading and a 30-minute maintenance infusion using 1 of the following dosing regimens: placebo then placebo (n = 12); 0.01 then 0.002 mg/kg (n = 12); 0.02 then 0.004 mg/kg (n = 12); or 0.03 then 0.006 mg/kg (n = 11). Ibutilide significantly increased QT and QTc intervals in a dose-related manner with mean increases ranging from 51 to 99 ms, but did not alter the PR interval or QRS duration. During ibutilide infusion, a few small but statistically significant changes from baseline in several hemodynamic variables were present. However, the changes in cardiac output, pulmonary artery or capillary wedge pressures, blood pressure, or heart rate in patients receiving ibutilide were not significantly different from the changes in patients receiving placebo. Thus, ibutilide did not cause clinically important adverse hemodynamic effects, even in patients with depressed ventricular function. One patient developed 2 episodes of nonsustained torsades de pointes during ibutilide. These results demonstrate that with careful monitoring for proarrhythmia, ibutilide can be used safely from a hemodynamic standpoint in the acute treatment of arrhythmias, even in patients with reduced ventricular function.

Adult↗
PubMed1999

Effects of sildenafil citrate on human hemodynamics.

Nitric oxide (NO) induces the formation of intracellular cyclic guanosine monophosphate (cGMP) by guanylate cyclase. Sildenafil, which selectively inhibits phosphodiesterase type 5 (PDE5) found predominantly in the corpora cavernosa of the penis, effectively blocks the degradation of cGMP and enhances erectile function in men with erectile dysfunction. The NO-cGMP pathway also plays an important role in mediating blood pressure. It is, therefore, possible that the therapeutic doses of sildenafil used to treat erectile dysfunction may have clinically significant effects on human hemodynamics. Three studies were undertaken to assess the effects of intravenously, intra-arterially, and orally administered doses of sildenafil on blood pressure, heart rate, cardiac output, and forearm blood flow and venous compliance in healthy men. A fourth study evaluated the hemodynamic effects of intravenous sildenafil in men with stable ischemic heart disease. In healthy men, significant (p <0.01) decreases in supine systolic and diastolic blood pressures were observed with intravenous sildenafil (20, 40, and 80 mg) at the end of the infusion period when plasma levels of sildenafil were highest (mean decreases from baseline of 7.0/6.9 and 9.2/6.7 mm Hg, for the 40- and 80-mg doses, respectively). These changes were transient and not dose related. Modest reductions in systemic vascular resistance also were observed (maximum decrease 16%), although heart rate was not affected by sildenafil administration when compared with placebo. Single oral doses of sildenafil (100, 150, and 200 mg) produced no significant changes in cardiac index from 1-12 hours postdose between placebo- and sildenafil-treated subjects. The approved dosage strengths of sildenafil citrate are 25 mg, 50 mg, and 100 mg. The 80-mg intravenous dose and the 200-mg oral dose of sildenafil produced comparable plasma levels at twice the maximum therapeutic dose (recommended range, 25-100 mg). After brachial artery infusion of sildenafil (up to 300 microg/min), there was a modest vasodilation of resistance arteries and a reversal of norepinephrine-induced preconstriction of forearm veins. These hemodynamic effects were similar to but smaller in magnitude than those of nitrates. In a small pilot study of men with ischemic heart disease, decreases from baseline in pulmonary arterial pressure (-27% at rest and -19% during exercise) and cardiac output (-7% at rest and -11% during exercise) were observed after 40-mg intravenous doses of sildenafil. Sildenafil was well tolerated by subjects and patients in all studies, with headache and other symptoms of vasodilation the most commonly reported adverse effects of treatment. Modest, transient hemodynamic changes were observed in healthy men after single intravenous or oral doses of sildenafil even at supratherapeutic doses. In men with stable ischemic heart disease, sildenafil produced modest effects on hemodynamic parameters at rest and during exercise.

Administration, Oral↗
PubMed1992

Maternal and fetal hemodynamic effects of autologous blood donation during pregnancy.

OBJECTIVES: Our objectives were to describe the maternal and fetal hemodynamic impact of a 1 U acute blood loss during pregnancy and to compare the hemodynamic responses of pregnant women with those of nonpregnant controls. STUDY DESIGN: With Doppler techniques cardiac output and total peripheral vascular resistance were determined in 16 pregnant women in the third trimester and in 16 nonpregnant volunteers before and during orthostatic stress, before and after donation of 450 ml of whole blood. In pregnant women the fetal umbilical artery systolic/diastolic ratio was also determined. Data were subjected to multiple logistic regression analysis. RESULTS: In both groups orthostasis provoked significant decreases in cardiac output and increases in total peripheral vascular resistance. The hemodynamic effects of blood loss were less pronounced and did not significantly change the hemodynamic response to orthostasis in either group. Neither orthostasis nor blood loss caused significant changes in the umbilical systolic/diastolic ratio. CONCLUSION: These data support the hemodynamic safety of uncomplicated autologous blood donation during late pregnancy.

Blood Donors↗
PubMed2002

A comparison of the in vivo performance of the 19-mm St. Jude Medical Hemodynamic Plus and 21-mm standard valve.

BACKGROUND: In the present study we analyzed the in vivo performance of the 19-mm St. Jude Medical Hemodynamic Plus aortic prosthesis (19HP), evaluated the midterm performance of 19HP in the aortic position, and compared the implantability and hemodynamic characteristics of this valve with those of the 21-mm standard St. Jude Medical valve (21SD) in adult patients with aortic stenosis and a narrowed aortic annulus. METHODS: From February 1994 to December 1999, 60 patients who underwent isolated aortic valve replacement with either the 19HP (n = 31) or the 21SD (n = 29) were studied. Comparison between the two models included analysis of early and late mortality and morbidity. Pre- and postoperative echocardiography was performed in all patients to evaluate and compare the hemodynamic performance of both prosthetic valves. The postoperative serum lactic dehydrogenase activity was measured in both groups of patients as an indicator of hemolysis. RESULTS: The mean body surface area was 1.46 +/- 0.16 m2 in the 19HP group and 1.49 +/- 0.13 m2 in the 21SD group (p = 0.1577). Other than female dominance in the 19HP group, there was no statistically significant difference between the two groups in terms of preoperative variables (age, preoperative pressure gradients, and New York Heart Association functional class). The average postoperative peak pressure gradient was 23.3 +/- 10.5 mm Hg in the 19HP group and 27.9 +/- 9.9 mm Hg in the 21SD group (p = 0.0666). There was no hospital death in either group. Six-year follow-up was completed in both groups of patients. Late death occurred in 1 patient in the 19HP group (1.09% per patient-year). Actuarial survival at 6 years was 92.3% +/- 7.4% in the 19HP group, and 100% in the 21SD group (p = 0.33). The linearized complication rate was 1.09% per patient-year and 1.02% per patient-year for thromboembolism, and 1.09% per patient-year and 1.02% per patient-year for anticoagulant-related hemorrhage in the 19HP group and the 21SD group, respectively. Freedom from all complications at 6 years did not show any significant difference between the two groups (p = 0.54). Although left ventricular mass indices decreased significantly after aortic valve replacement in both groups (19HP group, p = 0.0002; 21SD group, p = 0.0006), there were no significant differences in the two indices between the groups after aortic valve replacement (p = 0.999). There was no significant difference in the lactic dehydrogenase level between the two groups (p = 0.4915). CONCLUSIONS: In vivo hemodynamic performance of the 19HP valve as well as the early and intermediate clinical outcome up to 6 years was satisfactory and corresponded closely to that of the 21SD valve in adult patients. The 19-mm Hemodynamic Plus model can be recommended in patients with a measured 19-mm annulus and this valve will minimize the need for the aortic annular enlargement procedure.

Aortic Valve↗
PubMed1987

Nitrous oxide for blood pressure control after coronary artery surgery: a dose-response hemodynamic study in postoperative patients.

The inhaled anesthetic nitrous oxide is used for sedation in the coronary care unit and has been advocated as an antihypertensive agent in patients after a cardiac operation. To delineate the hemodynamic effects of nitrous oxide after cardiac surgery, we studied 11 patients with a mean age of 63 years who had undergone isolated coronary artery bypass grafting. All patients had major coronary artery disease and normal preoperative hemodynamic function. When patients were in stable condition in the intensive care unit, hemodynamic measurements were made at an inspired oxygen concentration of 40% with progressive doses of nitrous oxide (0, 10, 20, 40, and 60%). Measured and calculated hemodynamic data were compared using analysis of variance. Nitrous oxide caused significant decreases in mean arterial pressure in a dose-related fashion; pressure fell 6 mm Hg at 10% nitrous oxide and 11 mm Hg at 60% nitrous oxide (6 and 13% decreases). These changes were not associated with significant alteration in pulmonary artery pressure or cardiac index. Left ventricular stroke work index decreased significantly with the administration of nitrous oxide. We conclude that, in patients with normal hemodynamic and ventricular function, the administration of nitrous oxide for its sedative and antihypertensive effects is safe in the postoperative period and may be useful, especially in patients who are candidates for early extubation.

Aged↗
PubMed1997

Hemodynamic performance of small aortic valve bioprostheses: is there a difference?

BACKGROUND: There is the potential for left ventricular outflow obstruction when small aortic valve bioprostheses are employed in normal-sized or large adults. It has been hoped that bovine pericardial valves would improve hemodynamic performance in the smaller tissue valve sizes. METHODS: To determine in vivo hemodynamic performance of heterograft aortic valve prostheses, we analyzed echocardiographic data from patients receiving 21- or 23-mm Carpentier-Edwards pericardial, Medtronic Intact, and Carpentier-Edwards porcine bioprostheses. In addition, data from 19-mm Carpentier-Edwards pericardial valves were included for comparison of hemodynamic performance between valve sizes. Doppler echocardiography was performed in 151 patients within 2 weeks of operation. Left ventricular outflow gradient was derived from continuous Doppler measurements of flow velocity, and effective orifice area was calculated by the continuity equation. RESULTS: There were statistically significant differences in hemodynamic performance of different sized prostheses for each valve type (effective orifice area, p < 0.01; valvular gradient, p < 0.03). There were, however, no significant differences in effective orifice area or mean gradient for different valve types within each size category. CONCLUSIONS: The in vivo hemodynamic performance of these three different aortic valve heterograft bioprostheses is similar. Patient-prosthesis mismatch with heterograft prostheses, as demonstrated by the indexed effective orifice area can be avoided by appropriate sizing and use of annular enlarging techniques when necessary.

Adult↗
PubMed2003

Central alpha-adrenergic receptors and corticotropin releasing factor mediate hemodynamic responses to acute cold stress.

Behavioral stress is likely to contribute to the development of hypertension in susceptible individuals. We reported that hemodynamic response patterns to acute startle vary and that those patterns predict the predisposition of rats to sustained stress-induced elevations in arterial pressure. Since considerable evidence suggests that central catecholamines and corticotropin releasing factor (CRF) contribute to the regulation of arterial pressure and the development of hypertension, we investigated the role of central alpha-adrenergic receptors and CRF in mediating different hemodynamic response patterns to acute cold water stress in conscious rats. Rats were instrumented for arterial pressure, heart rate and cardiac output determination and for intracerebroventricular (icv) administration of selective antagonists. After acclimation to a water tight cage, ice water (1 cm deep) was rapidly added then drained 1 min later. Although the early startle response to cold water stress elicited a pressor response in all rats, the hemodynamic response pattern varied between rats. Vascular responders (n=19) had an initial considerable increase in systemic vascular resistance and a decrease in cardiac output. In contrast, mixed responders (n=11) had a smaller increase in vascular resistance and an increase in cardiac output. Pretreatment with phentolamine (30 microgram/5 microliter, icv, n=8), prazosin (10 microgram/5 microliter, icv, n=12) or alpha-helical CRF(9-41) (10 microgram/5 microliter, icv, n=9) prevented the decrease in cardiac output elicited by acute cold water stress in vascular responders without affecting mixed responders. Yohimbine (3 microgram/5 microliter, icv, n=8) pretreatment did not alter hemodynamic responses. Therefore, we conclude that central alpha(1)-adrenoceptors and CRF mediate the specific hemodynamic response patterns to acute startle and may be responsible for the predisposition to develop hypertension in vascular responders.

Adrenergic alpha-Antagonists↗
PubMed1997

Regional assessment of tissue oxygenation and the temporal evolution of hemodynamic parameters and water diffusion during acute focal ischemia in rat brain.

We assessed the temporal and spatial correlation between perfusion deficits and tissue damage in the first hours of focal cerebral ischemia in the rat. Repetitive dynamic susceptibility contrast-enhanced ('bolus track') and diffusion-weighted (DW) MRI, performed from ca. 0.5 up to 6 h after intraluminal middle cerebral artery occlusion (MCA-O), allowed the determination of the time course of various hemodynamic parameters and ischemic tissue damage in specific brain regions. In addition, blood oxygenation level dependent (BOLD) MRI combined with a respiratory challenge provided complementary information on brain hemodynamics. Within the territory of reduced blood flow, the degree of the hemodynamic disturbances was heterogeneous. Interestingly, the spatial pattern of perfusion deficiencies remained essentially the same from ca. 0.5 to 6 h post-MCA-O. However, the area and the extent of ischemic tissue damage, as expressed by reductions in the apparent diffusion coefficient (ADC) of tissue water, tended to progress with increasing occlusion time. Different ADC profiles correlated with different degrees of hemodynamic disturbances. In the ischemic core, which showed severely compromized perfusion, the ADC dropped significantly within 1 h. In perifocal areas, ADC reductions were delayed and less pronounced. Data from the bolus track and BOLD MRI experiments revealed the existence of residual flow, particularly in perifocal regions. Our data point to a time-dependent change in the relationship between ADC reductions and hemodynamic alterations and, therefore, agree with the concept of a progressively increasing perfusion threshold for ischemic tissue damage as a function of time of ischemia.

Animals↗
PubMed1996

The peroxynitrite product 3-nitro-L-tyrosine attenuates the hemodynamic responses to angiotensin II in vivo.

Peroxynitrite is a potent oxidant formed endogenously by the near diffusion-limited reaction of nitric oxide with superoxide anion. Peroxynitrite specifically adds a nitro group to the ortho position of the phenolic ring of free and protein-associated tyrosines to form the stable product 3-nitro-L-tyrosine. Systemic administration of 3-nitro-L-tyrosine markedly inhibits the subsequent hemodynamic responses to alpha 1- and beta-adrenoceptor agonists in anesthetized rats. Angiotensin II is an important modulator of vascular tone. The vasoconstrictor effects of this hormone are known to involve the release of catecholamines from sympathetic tissues. In the present study, we examined whether 3-nitro-L-tyrosine (2.5 mumol/kg i.v.) would attenuate the hemodynamic responses produced by angiotensin II (0.1-1.0 microgram/kg i.v.). Angiotensin II produced increases in mean arterial pressure, and renal and mesenteric vascular resistances, but no changes in hindquarter vascular resistance. The pressor and renal and mesenteric vasoconstrictor responses produced by angiotensin II were significantly attenuated 30-60 min following the administration of 3-nitro-L-tyrosine. Further attenuation of these responses was evident 120-180 min following the administration of 3-nitro-L-tyrosine. The alpha 1-adrenoceptor antagonist prazosin also diminished the pressor and renal and mesenteric vasoconstrictor responses produced by angiotensin II. These results demonstrate that 3-nitro-L-tyrosine inhibits the hemodynamic responses to angiotensin II, possibly through the inhibition of alpha 1-adrenoceptor-mediated events. The effect of 3-nitro-L-tyrosine on the hemodynamic action of angiotensin II raises the possibility that 3-nitro-L-tyrosine may be involved in the pathogenesis of the hemodynamic disturbances associated with inflammatory conditions, such as atherosclerosis, ischemia-reperfusion, and sepsis, where formation of peroxynitrite is favored.

Anesthesia↗
PubMed1997

Hemodynamic changes associated with reduction in total cholesterol by treatment with the HMG-CoA reductase inhibitor pravastatin.

Hemodynamic changes associated with the lowering of total cholesterol (TC) by the water-soluble HMG-COA reductase inhibitor pravastatin were investigated in 59 patients with hypercholesterolemia (TC level at least 220 mg/dl) who received pravastatin therapy for 6 months. The patients were divided into two groups according to the reduction in TC: a > or = 15% reduction group and a < 15% reduction group. The changes in hemodynamics were compared before and after pravastatin treatment. No changes in blood pressure, heart rate or aortic damping factor were found in either group. However, significant decreases in pulse wave velocity and total peripheral resistance, and increase in cardiac output were seen in the > or = 15% reduction group. All these hemodynamic parameters remained unchanged in the < 15% reduction group. The 12 patients with a clear pravastatin-induced reduction in TC maintained over a 5-year period showed no changes in blood pressure, heart rate or aortic damping factor, but the reductions in pulse wave velocity and total peripheral resistance, and increase in cardiac output were maintained. These changes in hemodynamics were not dependent on aortic elasticity, and appeared to result from improved peripheral hemodynamics. Lowering of TC levels by pravastatin results in improvement in the peripheral endothelium-dependent vasodilation disorder associated with hypercholesterolemia.

Anticholesteremic Agents↗
PubMed1998

Hemodynamic patterns of pharmacologically induced erection: evaluation by color Doppler sonography.

PURPOSE: Penile erection is achieved through hemodynamic mechanisms that can be assessed best with color flow imaging and Doppler waveform analysis. We performed dynamic studies using computer assisted analysis to assess the hemodynamic patterns of pharmacologically induced erection. MATERIALS AND METHODS: A total of 73 color Doppler ultrasound studies was performed in 66 patients with erectile dysfunction. Various blood flow parameters, including peak systolic velocity, end diastolic velocity, mean flow rate, resistive index and artery diameter, were observed continuously and recorded frequently for about 30 minutes after intracorporeal injection of papaverine/phentolamine/prostaglandin E1 mixture. A computerized Doppler waveform analysis of 3 curves or greater was performed for each recording to minimize error. A second injection was administered if the first injection failed to induce a rigid erection. Status of the erection was observed and recorded throughout the study. A computerized graph was generated for each corpus. RESULTS: After intracorporeal injection the time to reach normal or peak velocity varied from 1 to 24 minutes. Among 146 corpus units in 73 color Doppler ultrasound studies we observed the following hemodynamic patterns: I-normal maximal peak systolic velocity (35 cm. per second or greater), sustained; Ia-end diastolic velocity 0 or less with complete erection response (19 units); Ib-end diastolic velocity greater than 0 or incomplete erection response (14 units); II-normal maximal peak systolic velocity (35 cm. per second or greater), transient; IIa-end diastolic velocity 0 or less with complete erection response (21 units); IIb-end diastolic velocity greater than 0 or incomplete erection response (12 units); III-borderline maximal peak systolic velocity (30 to 35 cm. per second); IIIa-end diastolic velocity 0 or less with complete erection response (10 units); IIIb-end diastolic velocity greater than 0 or incomplete erection response (8 units); IV-low maximal peak systolic velocity (less than 30 cm. per second); IVa-end diastolic velocity 0 or less with complete erection response (24 units); and IVb-end diastolic velocity greater than 0 or incomplete erection response (38 units). CONCLUSIONS: Erection is a complex and dynamic process. A new classification of hemodynamic patterns is presented that aids in assessing and interpreting more thoroughly blood flow parameters to stratify more precisely the hemodynamic patterns of erectile dysfunction.

Adult↗
PubMed2002

Hemodynamic evaluation of the penile arterial system in patients with erectile dysfunction using power Doppler imaging.

OBJECTIVES: To assess the hemodynamics of the cavernous arteries (CAs) and helicine arteries (HAs) using power Doppler imaging (PDI) in patients with erectile dysfunction (ED). METHODS: Forty-two patients with and without a definite vascular component of ED were examined by PDI. The hemodynamic variables of the CAs and HAs were measured after intracavernous injection of 20 microg of prostaglandin E(1) . RESULTS: The CAs and HAs were visualized clearly and could be evaluated by PDI after prostaglandin E(1) injection in all patients. The hemodynamic variables of both the CAs and HAs differed between the groups. In the nonvasculogenic group, all 18 patients had normal cavernous arterial flow and achieved a full rigid erection. The mean peak systolic velocity in the HA was 19.5 cm/s on the right and 19.1 cm/s on the left. In the vasculogenic group, 43% of the 14 patients with normal cavernous arterial flow achieved a full rigid erection and had hemodynamic variables comparable to those in the nonvasculogenic group, but 57% failed to achieve a full rigid erection and their mean peak systolic velocity in the HA (8.5 cm/s, P = 0.0065 on the right; and 7.0 cm/s, P = 0.0024 on the left) was lower than in the nonvasculogenic group. Ten patients had reduced cavernous arterial flow and a full rigid erection could not be achieved. The mean peak systolic velocity (7.8 cm/s, P = 0.0009 on the right; and 6.5 cm/s, P = 0.0004 on the left) was lower than in the nonvasculogenic group. CONCLUSIONS: PDI is useful for evaluating the hemodynamics of the penile arterial system in patients with ED. Our data suggest that abnormalities of the HA contribute to ED.

Adult↗
PubMed2003

Hemodynamic effects of sildenafil in patients with stable ischemic heart disease.

BACKGROUND: Recently the new specific phosphodiesterase-5 inhibitor sildenafil was introduced into therapy for erectile dysfunction. The hemodynamic effects of sildenafil may be potentially hazardous for patients with cardiac disease. Sildenafil has been reported to augment the hypotensive effects of nitrates. There is sparse information regarding the systemic and pulmonary hemodynamic effects of a single oral dose of sildenafil in patients with stable angina. METHODS: Male patients referred for coronary angiography with diagnosis of chronic stable angina were enrolled in this study to assess the acute hemodynamic effects of sildenafil. Patients receiving long-acting or sublingual nitrates for the last 6 h before the study were excluded. Hemodynamic measurement were taken during right and left heart catheterization in the basal state and 60 min after 50 mg of oral sildenafil. RESULTS: Twelve patients (age 53+/-7 years) were studied. All had stable angina CCS class II or III. Four had previous myocardial infarction. By coronary angiography, seven patients had at least one coronary artery with >70% stenosis, four had at least one with 50-70% stenosis, and one had only intimal irregularities. There were no significant effects of sildenafil on systemic or pulmonary arterial pressure, left ventricle end diastolic pressure, cardiac output, and systemic or pulmonary vascular resistance (P>0.05 for all). No adverse events were observed. CONCLUSION: A single oral dose of sildenafil had no significant hemodynamic effect in supine patients with stable angina. Isolated administration of sildenafil does not appear to be associated to adverse cardiovascular effects.

Adult↗
PubMed1994

Effects of octreotide on postprandial systemic and hepatic hemodynamics in patients with postnecrotic cirrhosis.

The effects of octreotide on postprandial hemodynamic responses were evaluated in 20 patients with postnecrotic cirrhosis. They were randomly assigned to receive either a 100-micrograms bolus with a 100-micrograms/h infusion of octreotide or a placebo. Placebo administration did not affect any of the hemodynamic values. However, after a liquid meal of 500 kcal, postprandial increases in the hepatic venous pressure gradient and hepatic blood flow were observed in patients receiving placebo, while the systemic hemodynamic values remained unchanged. In contrast, in patients receiving octreotide, the hepatic blood flow was significantly decreased 30 min after administration, while the hepatic venous pressure gradient and the systemic hemodynamic values were not affected. After ingestion of a meal, the mean values of the hepatic blood flows were not significantly different from basal values. Moreover, the wedged hepatic venous pressure, the hepatic venous pressure gradient and the systemic hemodynamic values were not affected by meal ingestion. However, during octreotide infusion, hepatic blood flow 30 min after the meal had a tendency to increase compared to before the meal. In conclusion, octreotide inhibited the postprandial increase in portal pressure in patients with postnecrotic cirrhosis. In addition, octreotide decreased hepatic blood flow in the fasting state. When given before a meal, the increase in blood flow induced by the meal restored the hepatic blood flow to basal levels.

Adult↗
PubMed1998

[Hemodynamic deterioration in patients submitted to ablation of the atrioventricular node].

INTRODUCTION: Radiofrequency ablation of the atrioventricular conduction system has become an established therapy for patients with drug-refractory atrial fibrillation. We observed 14 patients with hemodynamic deterioration related to worsening of mitral regurgitation after the procedure. PATIENTS AND METHODS: We retrospectively evaluated 256 consecutive patients with drug-refractory atrial fibrillation referred for radiofrequency ablation of the AV node and implantation of a pacemaker. Because we found hemodynamic deterioration related to worsening mitral regurgitation, we compared the clinical history, electrophysiologic and echocardiographic data from the patients with hemodynamic deterioration and worsening mitral regurgitation (group A) with those without hemodynamic deterioration (group B). RESULTS: Fourteen out of 256 patients (group A) undergoing ablation of the atrioventricular conduction system deteriorated with acute pulmonary edema (3 patients) or congestive heart failure (11 patients) at a mean of 6 weeks after the ablation procedure. Four of these patients were referred for mitral valve surgery. The length of the procedure and the number of applications during ablation were similar in both groups. Compared with group B patients, group A patients had significantly higher left ventricular end-diastolic diameters (64 +/- 6 mm vs 56 +/- 9 mm; p < 0.05) at baseline despite similar left ventricular end-systolic diameters, fractional shortening and grade of mitral regurgitation (1.15 +/- 1.05 vs 1.11 +/- 0.97). Moreover, whereas no change was observed in left ventricular end-diastolic diameter, left ventricular end-systolic diameter, fractional shortening and grade of mitral regurgitation in group B patients after ablation, group A patients experienced a significant increase in left ventricular end-diastolic diameter (64 +/- 6 mm vs 72 +/- 9 mm; p < 0.01) and grade of mitral regurgitation (1.15 +/- 1.05 vs 2.90 +/- 1.15; p < 0.01). In patients operated on no ablation related structural damage to the mitral valve apparatus could be detected. The worsening of the mitral regurgitation was related to dilation of the mitral valve annulus. CONCLUSIONS: Hemodynamic deterioration together with progression of mitral regurgitation is a potential complication of ablation of the atrioventricular conduction system.

Adult↗