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PubMed2005

Immersion in warm water induces improvement in cardiac function in patients with chronic heart failure.

BACKGROUND: The effects of immersion and training of patients with chronic heart failure (CHF) in warm water has not been thoroughly investigated. The aim of this study was to assess the acute hemodynamic response of immersion and peripheral muscle training in elderly patients with CHF. METHODS: Thirteen CHF patients and 13 healthy subjects underwent echocardiography on land and in a temperature-controlled swimming pool (33-34 degrees C). RESULTS: Rest. Heart rate decreased (CHF, p=0.01; control, p=0.001) and stroke volume increased (CHF, p=0.01; control, p=0.001) during water immersion in both groups, with no change in systolic or diastolic blood pressure. Ejection fraction (p<0.05) and transmitral Doppler E/A ratio (p=0.01) increased in the CHF group, with no changes in left ventricular volumes. The healthy subjects had similar responses, but also displayed an increase in cardiac output (p<0.01) and left ventricular volumes (p<0.001). Exercise. Cardiac output and systolic blood pressure increased significantly in water, in both groups. CONCLUSION: A general increase in early diastolic filling was accompanied by a decrease in heart rate, leading to an increase in stroke volume and ejection fraction in most patients with CHF during warm water immersion. These beneficial hemodynamic effects might be the reason for the previously observed good tolerability of this exercise regime.

Aged↗
PubMed1993

Effects of renin inhibitor A-72517 on hemodynamics and cardiac function in sodium-depleted dogs.

A-72517 is a potent inhibitor of human renin (IC50 = 1.0 nmol/L, pH 7.4 in plasma) and, aside from displaying modest activity against canine plasma renin (IC50 = 110 nmol/L), has been shown to be orally active in the dog and other animals. Renin inhibitors, in general, are presumed to exert their hypotensive effect through a reduction in total peripheral resistance. To elucidate the hemodynamic mechanism of action of this new dipeptidic renin inhibitor, the cardiac and systemic hemodynamic effects of A-72517 were studied in sodium-depleted, pentobarbital-anesthetized dogs. Each dog received either vehicle (n = 8) or a single dose (n = 8/dose) of A-72517 administered intravenously as a priming bolus followed by a 30 min constant infusion; infusion doses were 0.01, 0.05, and 0.1 mg/kg/min. A-72517 elicited significant (P < .05) dose-related reductions in mean arterial pressure (MAP) and systemic vascular resistance (SVR) compared to baseline values and the vehicle-treated group, and the recoveries of MAP and SVR were also dose-related. Plasma renin activity, measured by radioimmunoassay, was nearly completely suppressed during drug infusion at all doses. The hypotensive responses did not alter cardiac output nor did they induce reflex tachycardia at any dose. Left ventricular dP/dtmax did not change during infusion of A-72517, but, when corrected for changes in afterload, showed dose-related increases with drug treatment. Moreover, left ventricular end-diastolic pressure and pulmonary arterial wedge pressure were significantly reduced at the high dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Improved cardiac function with glucose-insulin-potassium after aortocoronary bypass grafting.

To assess the effectiveness of metabolic support for the heart in patients with refractory heart failure after hypothermic ischemic arrest for aortocoronary bypass grafting we assigned 22 patients to receive either intravenous glucose (50%), insulin (80 IU/L), and potassium (100 mEq/L) at a rate of 1 mL/kg/h for up to 48 hours (GIK) or glucose (5%) and NaCl (0.225%) at the same rate (control). All patients started out with a mean cardiac index of less than 3.0 L/min/m2, were on intraaortic balloon pump assistance, and required inotropic drugs. At 12 and 24 hours cardiac index had increased significantly in the GIK group when compared with the control group (3.6 and 3.4 versus 2.5 and 2.7 L/min/m2, respectively). Time on the intraaortic balloon pump (39 versus 61 hours) and requirements for inotropic drug support were significantly less in GIK group than in the control group. All 11 GIK patients could be weaned from intraaortic balloon pump assistance. At 30 days after operation survival was 10/11 in the GIK group, compared with 7/11 in the control group. We conclude that GIK is both safe and effective in the treatment of refractory left ventricular failure after aortocoronary bypass grafting. The exact mechanism for the beneficial effect of GIK on myocardial contractility remains to be elucidated.

Aged↗
PubMed1988

Regional blood flows and cardiac function changes induced by angiotensin II in conscious dogs.

Hemodynamic properties of angiotensin (ANG) II 1, 5, 10 and 100 ng/kg i.v. and 10, 100 and 1000 ng/kg i.v.t. were assessed in conscious dogs. ANG II i.v. produced a dose-dependent pressor response (59 +/- 5-124 +/- 16 mmHg) and renal vasoconstriction (1.3 +/- 0.4-96 +/- 32 mmHg/ml/min). Ganglionic blockade (chlorisondamine 2 mg/kg i.v.) diminished mean arterial responses without altering peptide effects on renal circulation. At the highest dose, ANG II i.v. induced cardiac stimulation: increased heart rate (75 +/- 4-115 +/- 6 beats/min), cardiac output (2.0 +/- 0.1-2.4 +/- 0.2 l/min), dP/dt (2308 +/- 181-2773 +/- 173 mmHg/sec) and coronary blood flow (49 +/- 10-96 +/- 23 ml/min). Although with chlorisondamine cardiac response was more pronounced, subsequent beta blockade abolished it. Concomitantly, an isolated increase in plasma epinephrine was recorded (63 +/- 8-1505 +/- 354 pg/ml). A pressor response (59 +/- 8-89 +/- 13 mmHg) and renal vasoconstriction (1.1 +/- 0.1-2.2 +/- 0.5 mmHg/ml/min) were also produced by ANG II i.v.t. at the highest dose. These centrally mediated changes were prevented by chlorisondamine. Our study demonstrates 1) i.v. ANG II-mediated pressor responses are dependent on direct and indirect components, the relative contribution of each being dependent on the regional circulation; ANG II i.v. also produced a biphasic cardiac response--an initial centrally mediated depression and a secondary stimulation dependent on epinephrine via cardiac beta receptors and 2) i.v.t. ANG II-mediated pressor effects are essentially indirect. Finally, no evidence was found to support the role of vasopressin in ANG II effects.

Angiotensin II↗
PubMed1992

Allergic granulomatosis and angiitis with severe cardiac disease: a case in which cardiac function was extremely improved by long-term steroid therapy.

A 38-year-old man with a history of bronchial asthma developed marked eosinophilia, mononeuritis multiplex and transient pulmonary infiltration. Pathological findings from the lung and nerve biopsy were helpful in determining the diagnosis as allergic granulomatosis and angiitis (AGA). Echocardiogram indicated dilation of the left ventricle with impaired systolic contraction. Coronary arteriography demonstrated significant stenosis only in the peripheral segment of the circumflex artery. After 1 year of corticosteroid therapy, echocardiogram revealed improvement of left ventricular contractility evaluated by ejection fraction (from 28% to 67%). To our knowledge, no previous reports have described amelioration of severe cardiac lesions during long-term steroid treatment in patients with AGA.

Adult↗
PubMed2002

Recovery of cardiac function after living-donor lung transplantation in a patient with primary pulmonary hypertension.

Legislation for brain death and organ transplantation was passed in Japan in 1997, but there is still a great shortage of brain-death donors. Primary pulmonary hypertension (PPH) is a progressive disease that is usually followed by death within 5 years of diagnosis. Continuous infusion of prostacyclin is effective, but some patients will ultimately require heart-lung or lung transplantation. The first case of bilateral living-donor lobar lung transplantation (LDLLT) for PPH in Japan is reported. The recipient was a 19-year-old woman who was diagnosed as PPH at the age of 14 years and began intravenous prostacyclin therapy. Initially her symptoms improved, but she returned to New York Heart Association class IV in 2000. In January 2001, she underwent bilateral LDLLT. Postoperative echocardiography showed that the right ventricular diameter had decreased and septal wall motion had normalized, resulting in a round-shaped left ventricle. Right heart catheterization demonstrated that cardiac output and pulmonary arterial pressure had normalized. The right ventricular ejection fraction improved from 15% to 77%. The patient was discharged from hospital after 60 days postoperatively. LDLLT will become one of the options in Japan for end-stage PPH.

Adult↗
PubMed1997

Ventilation by external high-frequency oscillations improves cardiac function after coronary artery bypass grafting.

OBJECTIVE: To compare the effects of ventilation with intermittent positive pressure and external high frequency oscillation by the Hayek Oscillator during the first 5 h after coronary artery bypass grafting. METHODS: Eleven patients were randomized to intermittent positive pressure ventilation throughout the observation period (5 h), while 13 patients were initially ventilated with intermittent positive pressure ventilation, then by external high-frequency oscillations for 4 h, changing to positive pressure ventilation for the last hour. RESULTS: Cardiac index, stroke volume index, right ventricular stroke work index, right ventricular end-diastolic volume index and mixed venous oxygen saturation were significantly increased during ventilation with external high-frequency oscillations, and arteriovenous oxygen content difference was significantly reduced. There were no significant inter- or intragroup differences in fluid accumulation, mean arterial blood pressure, arterial blood gases, pulmonary artery pressure, central venous pressure, pulmonary capillary wedge pressure, heart rate, systemic vascular resistance index, pulmonary vascular resistance index, intrapulmonary shunt fraction, right ventricular ejection fraction, right ventricular end-systolic volume index and left ventricular stroke work index. CONCLUSIONS: Ventilation by external high-frequency oscillations increases cardiac index and improves tissue perfusion. The increased pumping of the heart is probably caused by changes of the intracardiac pressure-volume relationship. The Hayek Oscillator may have distinct cardiovascular benefits as ventilatory assistance in postoperative cardiac surgical patients.

Aged↗
PubMedDate not supplied

Cardiac function after orthotopic heart transplantation: response to postural changes, exercise, and beta-adrenergic blockade.

To prospectively assess the response of orthotopic heart transplant recipients to exercise before and after beta-adrenergic blockade, we investigated 35 orthotopic heart recipients, all with clinically stable conditions and without rejection, and five control, healthy subjects. Radionuclide angiography was performed at rest and during supine bicycle exercise, before and after beta-blockade. At rest, heart rate, systolic and diastolic pressures, and end-systolic volume were higher, whereas the end-diastolic volume and stroke volume indexes, cardiac index, and ejection fraction were significantly lower in the transplant recipients than in healthy control subjects. During exercise, before beta-blockade, transplant recipients attained a lower maximal heart rate and smaller increments in heart rate than did the control subjects. The cardiac index increased during exercise because of an increase in stroke volume (43%) and heart rate (32%) in the transplant recipients and nearly exclusively (93%) because of an increase in heart rate in the normal subjects. After beta-blockade, the ejection fraction, the stroke volume, and the cardiac index fell significantly at rest in both groups. The fall in ejection fraction was greater in the transplant recipients than in the control subjects (-16% +/- 12.6% versus -5.4% +/- 2.6%, respectively; p = 0.0002). After beta-blockade, lower maximal heart rate, ejection fraction, and cardiac index were achieved during exercise in both groups. The peak exercise cardiac index was 42% lower in transplant recipients than in control subjects after beta-blockade. Thus, cardiac performance during exercise is impaired in orthotopic heart transplant recipients. Acute beta-adrenergic blockade accentuates the impairment in ventricular performance and appears to be detrimental in these patients.

Adolescent↗
PubMed2006

[Peculiarities of regulation of cardiac function in some mammals].

We studied acetylcholine induced changes of action potentials (AP) in ventricles and atria of bat, hedgehog, yakut ground squirrel, and laboratory mice. In atria of all these species of mammals acetylcholine caused pronounced dose dependent shortening of AP. However sensitivity of ventricles of studied animals to acetylcholine was different. Acetylcholine induced AP shortening was 29.4, 42.1, 6.6 and 11% in ventricles of bat, hedgehog, laboratory mice and ground squirrel, respectively. Ventricles of none of previously studied mammals had sensitivity to acetylcholine comparable by magnitude to acetylcholine sensitivity which we found in hedgehog and bat. It is suggested that these animals have unique nervous regulation of cardiac action, principally different from that of other mammals, which do not require parasympathetic regulation of ventricles.

Acetylcholine↗
PubMed1993

[Cardiac function following left ventricular aneurysm repair--comparison between patch reconstruction and direct closure methods].

Left ventricular function was compared between two groups of patients who underwent patch reconstruction or direct closure of the ventricular wall following resection of a post-infarction left ventricular aneurysm (LVA). There were 15 and 9 patients in the respective groups. Coronary artery bypass grafting was additionally performed in 8 patients (53%) in the patch reconstruction group and 5 patients (56%) in the direct closure group. The size of the patch used for patch reconstruction (including the suture line) was 57 +/- 19% of the resected area. Before and 1-2 months after surgery, equilibrium RI angiography and cardiac catheterization were performed to assess the following hemodynamic parameters: ejection fraction (EF) at rest and during exercise, left ventricular end-diastolic pressure (LVEDP), left ventricular end-diastolic volume index (LVEDVI), cardiac index (CI) and mean pulmonary artery pressure (m-PAP). Preoperatively, there were no differences in each parameter between the two groups. Postoperatively, there were significant improvements in the EF at rest and during exercise (p < 0.01), LVEDVI (p < 0.01) and the LVEDP (p < 0.05). However there no significant changes in CI or m-PAP following the operation. There were also no significant differences observed in the postoperative values between the two groups. However, based upon postoperative left ventriculograms, patch reconstruction was significantly superior to direct closure for reconstruction of a septal aneurysm.

Aged↗
PubMed1999

Autoantibodies activating human beta1-adrenergic receptors are associated with reduced cardiac function in chronic heart failure.

BACKGROUND: Autoantibodies against synthetic peptides of beta-adrenergic receptors have been observed in human cardiomyopathy. However, it has never been shown that such antibodies really interact with native human beta-adrenergic receptors, nor has the clinical impact of such an interaction been investigated in larger groups of patients. METHODS AND RESULTS: We screened 104 patients with dilated or ischemic cardiomyopathy (NYHA functional classes II to IV) and 108 healthy subjects for IgG antibodies reacting with beta-receptor peptides. Such IgGs were further analyzed for binding and functional interactions with native recombinant human beta-adrenergic receptors. Antibodies reacting with synthetic receptor peptides were present in 51% of the patients. However, only a subgroup directed against the second extracellular receptor domain also recognized native human beta-adrenergic receptors situated in a cell membrane. All antibodies of this subgroup impaired receptor ligand binding and enhanced receptor-mediated signaling, which could be blocked by 5 micromol/L bisoprolol in vitro. Their prevalence was 1% in healthy subjects and 10% in ischemic cardiomyopathy, whereas it amounted to 26% in dilated cardiomyopathy and was associated with a significantly poorer left ventricular function. CONCLUSIONS: Our data show that activating autoantibodies against human beta-adrenergic receptors exist in approximately 25% of patients with dilated cardiomyopathy. Counteraction of such autoantibodies might contribute to the beneficial effects of beta-adrenergic receptor blockade in chronic heart failure.

Antigen-Antibody Reactions↗
PubMed1999

Correlation of heart rate variability with cardiac functional and metabolic variables in cyclists with training induced left ventricular hypertrophy.

OBJECTIVE: To examine the correlation between heart rate variability and left ventricular mass in cyclists with an athlete's heart. METHODS: Left ventricular mass and diastolic function were determined at rest and myocardial high energy phosphates were quantified at rest and during atropine-dobutamine stress in 12 male cyclists and 10 control subjects, using magnetic resonance techniques. Ambulatory 24 hour ECG recordings were obtained, and time and frequency domain heart rate variability indices were computed. RESULTS: In the cyclists, the mean of all RR intervals between normal beats (meanNN), the SD of the RR intervals, and their coefficient of variation were significantly greater than in control subjects (p < 0.01, p < 0.01, and p < 0.05, respectively). For cyclists and control subjects, only meanNN correlated with left ventricular mass (r = 0.48, p = 0.038). The heart rate variability indices that correlated with functional or metabolic variables were: meanNN v E/A peak (the ratio of peak early and peak atrial filling rate) (r = 0.48, p = 0.039); the root mean square of successive differences in RR intervals among successive normal beats v E/A area (ratio of peak early and peak atrial filling volume) (r = 0.48, p = 0.040); percentage of successive RR intervals differing by more than 50 ms v the phosphocreatine to ATP ratio at rest (r = 0.54, p = 0. 017); and the SD of the average RR intervals during all five minute periods v the phosphocreatine to ATP ratio during stress (r = 0.60, p = 0.007). CONCLUSIONS: Highly trained cyclists have increased heart rate variability indices, reflecting increased cardiac vagal control compared with control subjects. Left ventricular mass has no major influence on heart rate variability, but heart rate variability is significantly correlated with high energy phosphate metabolism and diastolic function.

Adult↗
PubMed1991

[Cardiac function during exercise in patients with coronary bypass surgery assessed by continuous ventricular function monitoring].

The response of left ventricular function during exercise and recovery after exercise was assessed in 52 patients with coronary artery bypass surgery by means of a radionuclide continuous ventricular function monitor. This system consists of 2 radionuclide detectors, recorder and a computer. After the equilibration of 20 mCi technetium 99m-labeled autologaous red blood cells into the intravascular space, the beat by beat radionuclide data were summed for 20-sec intervals to measure left ventricular ejection fraction (EF). Before surgery, the mean EF decreased with exercise from 51 +/- 9% to 45 +/- 11% (p less than 0.001). Cardiac response was divided into 4 types according to the profiles of the EFs during exercise. In 6 patients, EF continued to increase until maximal exercise (type A). In 10 patients, EF initially increased and then decreased in late exercise stages (type B). In 9 patients, EF did not change significantly during exercise (type C). In 27 patients, EF decreased throughout exercise (type D). After surgery, the mean EF increased with exercise from 53 +/- 10% to 60 +/- 13% (p less than 0.001). Thirty-five patients showed type A, 9 type B, 5 type C, and 3 type D. Two type D and 5 type B patients had occluded grafts or ungrafted coronary arteries. Four patients with complete revascularization including an internal thoracic artery and saphenous vein grafts showed type B. Three patients with extensive infarction and poor left ventricular function showed type C.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Effect of hyperparathyroidism on cardiac function in patients with end-stage renal disease.

Heart studies were carried out in 7 patients with end-stage renal disease (ESRD) who underwent parathyroidectomy for secondary hyperparathyroidism. The studies, which included echocardiography and equilibrium radionuclide angiography (ERNA), were performed prior to parathyroidectomy and 2 weeks, 3 months, and 6 months following it, on a nondialytic day. Heart rate decreased from 89.3 +/- 1.3 to 81.4 +/- 1.5 min-1 (p less than 0.001) following parathyroidectomy and returned to the initial level at 3- and 6-month examination. Cardiac output decreased from 3170 +/- 68 to 2943 +/- 57 ml/min (p less than 0.01) following parathyroidectomy and returned to basal level on 3 and 6-month determinations. End-diastolic dimension (EDD), end-systolic dimension (ESD), septal and posterior wall thickness and shortening fraction (SF) as measured by echocardiography were normal prior to parathyroidectomy and remained unchanged following it. Left ventricular ejection fraction (LVEF), end-diastolic and end-systolic volumes measured by ERNA did not change following parathyroidectomy. This study suggests that hyperparathyroidism has little effect on cardiac performance and, except for a short-lived decrease in heart rate and cardiac output, parathyroidectomy does not affect cardiac performance when performed in patients with preoperatively normal cardiac output.

Adult↗
PubMed1985

Nadolol in essential hypertension: effect on ambulatory blood pressure, renal haemodynamics and cardiac function.

Chronic administration of nadolol has been reported to reduce blood pressure either without or with a concomitant fall of renal blood flow. We therefore studied the effects of nadolol 80 mg once daily on ambulatory blood pressure, renal and systemic haemodynamics in patients with mild to moderate essential hypertension. Ten patients took part in this randomized, double-blind, placebo-controlled, crossover study, each phase of which lasted 4 weeks. Nadolol significantly reduced ambulatory blood pressure and heart rate, but had no effect on blood pressure variability. Cardiac output was significantly reduced by nadolol and total peripheral resistance increased but without reaching statistical significance. Despite the fall in blood pressure and cardiac output, renal blood flow and glomerular filtration rate remained unchanged. The fraction of cardiac output reaching the kidneys rose significantly and renal vascular resistance was significantly reduced. Body weight, urinary sodium excretion and urine flow rate remained unchanged. We conclude that nadolol 80 mg once daily lowers ambulatory blood pressure in patients with mild to moderate hypertension without impairment of renal blood flow, indicating a redistribution of cardiac output to the kidneys. The mechanism of the renal vasodilator effect of nadolol remains to be determined.

Adrenergic beta-Antagonists↗
PubMed1989

Assessment of the daily blood pressure load as a determinant of cardiac function in patients with mild-to-moderate hypertension.

The distribution of blood pressure (BP) values over the day and night was assessed in a group of 30 never previously treated patients with mild-to-moderate essential hypertension via 24-hour ambulatory BP monitoring. Elevated BP values during the awake hours (greater than 140/90 mm Hg) and sleeping hours (greater than 120/80 mm Hg) were used to calculate the total percentage of abnormal BP values (load) in each patient. The relationship between BP load and several indexes of hypertensive cardiac target organ involvement was compared to the relationships among office (casual), 24-hour average BP values, and cardiac indexes. Casual systolic and diastolic BP values did not correlate with left ventricular mass index, left atrial index, or peak left ventricular filling rate. Both 24-hour average BP and systolic and diastolic BP loads correlated with all indexes of cardiac target organ involvement. The BP loads were related to left ventricular mass index and left atrial index more strongly than were the mean 24-hour BP values; however, they were equally correlated for peak left ventricular filling rate. If greater than 40% of the ambulatory BP values were elevated, the likelihood of increased mass or decreased filling was greater than 61%, whereas if less than 40% of the BP values were elevated, the incidence of an abnormal cardiac test result decreased to less than 17%. These data show that the percentage of elevated BP values that includes both the awake and asleep periods is predictive of cardiac target organ involvement in patients with mild-to-moderate hypertension. Patients with mild hypertension who have more than 40% abnormal BP values should strongly be considered for antihypertensive therapy.

Adult↗
PubMedDate not supplied

[Systolic time interval as a means of evaluating the cardiac functional capacity in patients with and without heart insufficiency].

Determining the systolic time intervals in a non-invasive method which is easy to apply and inexpensive, and it can be repeated as many times as necessary. The patient is subjected to low psychic stress so that even elderly and sick patients may undergo it. The STI method may be applied to case control and the observation of the development of a disease following pharmacological treatment. The method makes it possible to differentiate between healthy persons and patients suffering from cardiac insufficiency, and concealed insufficiencies of the cardiac circulation may be detected. The STI interpretation must take into account those factors which have an effect on the STI length. The results can be considerably upgraded through the use of certain indices, PI being the main one. The PI index is of particular value if the effect of the treatment by glycoside medication is to be observed.

Aged↗

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