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A 55-year-old man came to the hospital because of chest pain, mostly occurring in the early morning at rest. He had to get isosorbide dinitrate intravenously with continuous infusion. Following ergonovine provocation test, total occlusion of mid-left anterior descending artery was identified with marked elevation of ST segment as exercise test showed despite isosorbide dinitrate.
BACKGROUND/AIM: The study was designed to assess to what extent portal hemodynamic parameters obtained by duplex Doppler ultrasonography may be substituted for the measurement of hepatic venous pressure gradient in evaluating the severity of portal hypertension and the response to medical treatment with beta-blockers or beta-blockers plus nitrates in patients with cirrhosis and portal hypertension. METHODS: In 39 of these patients hepatic venous pressure gradient was determined by hepatic vein catheterization, and portal blood flow velocity and the congestion index of the portal vein were measured by duplex Doppler ultrasonography. In 19 of these patients the changes in hepatic venous pressure gradient and in Doppler parameters were also assessed after chronic administration of nadolol. In 11 of the 19 patients the changes after chronic administration of nadolol plus isosorbide-5-mononitrate were also measured. RESULTS: In the whole series, no significant correlation was found between hepatic venous pressure gradient and duplex Doppler parameters, but, when the 12 patients with a patent para-umbilical vein were excluded, significant linear correlations were found between hepatic venous pressure gradient and portal blood velocity (r=-0.39; p=0.05) or congestion index (r=0.37; p=0.05). Considering together the changes induced by nadolol and nadolol plus isosorbide-5-mononitrate, no correlation was apparent between changes in duplex Doppler parameters and in hepatic venous pressure gradient. Agreement between hepatic venous pressure gradient and duplex Doppler parameters in defining good and poor responders was insufficient. CONCLUSIONS: These data suggest that portal blood velocity and the congestion index of the portal vein are related to portal hypertension in patients without a patent para-umbilical vein, but are of limited value in discriminating good responders from poor responders to medical treatment for portal hypertension.
The vasomotor response of proximal and distal angiographically normal coronary artery segments was studied in 12 patients with syndrome X, 17 age- and gender-matched patients with chronic stable angina and 10 control subjects with atypical chest pain and a normal coronary arteriogram. Ergonovine (300 micrograms by intravenous injection) and isosorbide dinitrate (1 mg by intracoronary injection) were administered to all patients. Computerized coronary artery diameter measurement (angiographically normal segments only) was carried out before and after the administration of ergonovine and nitrate. Baseline intraluminal diameters (mean +/- SEM) of proximal and distal coronary segments were not significantly different in control subjects and patients with syndrome X or coronary artery disease (proximal 2.88 +/- 0.19, 3.01 +/- 0.13 and 2.86 +/- 0.13 mm; distal 1.57 +/- 0.09, 1.70 +/- 0.10 and 1.61 +/- 0.06 mm, respectively). With ergonovine, proximal segments constricted by 10 +/- 2%, 7 +/- 2% and 11 +/- 3% and distal segments by 12 +/- 3%, 14 +/- 3% and 14 +/- 2% in control subjects and patients with syndrome X or coronary artery disease, respectively (p = NS). With isosorbide dinitrate, proximal coronary segments dilated by 11 +/- 2%, 10 +/- 2% and 8 +/- 2% (p = NS) and distal segments by 15 +/- 2%, 11 +/- 3% and 13 +/- 2% (p = NS) in control subjects and patients with syndrome X or coronary artery disease, respectively. Within groups, constriction in response to ergonovine and dilation in response to nitrate were not significantly different in proximal and distal segments.(ABSTRACT TRUNCATED AT 250 WORDS)
The objective of this study was to assess the influence of left ventricular (LV) geometric pattern on coronary vasomotion in patients with essential hypertension. We studied 34 hypertensive patients, who had never been treated, with angiographically normal coronary arteries. Patients were classified into four LV geometric patterns by echocardiography: normal, concentric remodeling, eccentric hypertrophy, and concentric hypertrophy. The responses of coronary vasomotion in left anterior descending artery to vasoactive agents (acetylcholine, isosorbide dinitrate, adenosine triphosphate) were examined using a Doppler guidewire and quantitative coronary angiography. The percent increase in coronary blood flow evoked with acetylcholine (endothelium-dependent vasomotion) showed lowest in concentric hypertrophy, followed by eccentric hypertrophy, concentric remodeling, and normal geometry. The significant linear relationship between acetylcholine-induced coronary blood flow and LV mass was noted. There was no difference in the percent increase in coronary blood flow evoked with isosorbide dinitrate (endothelium-independent vasomotion of conduit vessel) among the four groups. The percent increase in coronary blood flow evoked with adenosine triphosphate (endothelium-independent vasomotion of resistant vessel) was significantly lower in patients with concentric hypertrophy than in the other three groups. The results in this study suggest that coronary vasomotion may be associated with LV geometry in patients with hypertension. The endothelium-dependent vasodilation is impaired progressively as LV hypertrophy advances. The endothelium-independent vasodilation of microvessels is impaired only in concentric hypertrophy. This advanced abnormality of coronary vasomotion may contribute to the high cardiovascular morbidity and mortality in patients with concentric hypertrophy.
Anal ultra slow waves (USWs) have been described in a variety of anorectal disorders, all of which may be associated with constipation. We investigated whether they represent a marker for dyschezia and whether their occurrence can be modified. Manometric and endosonographic studies were performed in 25 patients with dyschezia, in 25 age- and sex-matched controls, and in an equal number of patients with hemorrhoids. Patients exhibiting ultra slow waves were repeatedly studied with and without local administration of isosorbide dinitrate. In addition, we determined whether stimulatory maneuvers modify the occurrence of USWs. Anal USWs were persistently found in 56% of patients with dyschezia, in 8% of patients with hemorrhoids, and in none of the healthy controls. They were stimulated by anal squeeze and completely abolished by local administration of isosorbide dinitrate. Ultra slow waves always occurred in conjunction with an increase in anal resting pressure and were tightly associated with a fluctuation in slow wave amplitude. Anal sphincter morphology was similar in patients with dyschezia and in controls. We conclude that anal USWs occur most frequently in patients with dyschezia and indicate smooth muscle dysfunction. Treatment directed at abolishing this motor phenomenon may represent a novel approach to the management of patients with dyschezia.
The pharmacokinetics and urinary recoveries of four isomeric mononitrates, L-isoidide mononitrate (L-IIMN), isosorbide-2-mononitrate (IS-2-MN), isomannide mononitrate (IMMN), and isosorbide-5-mononitrate (IS-5-MN), were investigated at an intravenous dose of 2 mg/kg in rats. All four compounds exhibited monoexponential kinetics at this dose. The volumes of distribution were similar for all four isomers and were estimated at about 1.0 liter/kg. The systemic clearances of L-IIMN, IMMN, IS-2-MN, and IS-5-MN were 65.1 +/- 13.0, 32.7 +/- 12.0, 11.0 +/- 2.3, and 8.23 +/- 1.82 ml/min/kg, respectively (P < 0.05, all pairwise comparisons). Free mononitrate in the urine accounted for 0.306 to 4.56% of the administered dose, while the recovery in conjugated forms (after glusulase hydrolysis) accounted for 42.8% of the IMMN dose and 7.70 to 14.5% of the dose of the remaining three isomers. The dose-dependent pharmacokinetics of three of the mononitrates were explored at selected higher doses which cause equivalent vasodilator responses, L-IIMN (22 mg/kg), IS-2-MN (100 mg/kg), and IS-5-MN (300 mg/kg). The clearances of L-IIMN, IS-2-MN, and IS-5-MN at these higher doses were 42.3 +/- 5.7, 6.38 +/- 0.59, and 3.33 +/- 0.62 ml/min/kg, respectively, all significantly less than those found at the 2 mg/kg dose. Typical Michaelis-Menten-type curvatures were observed in the concentration-time curves after IS-2-MN and IS-5-MN dosing. The pharmacokinetics of L-IIMN were also dose dependent, but they could not be described by simple Michaelis-Menten kinetics.
Hemolytic uremic syndrome (HUS) after transplantation is difficult to treat, and there is no consensus regarding optimal mode of treatment. We attached transdermal isosorbide tape as a nitric oxide (NO) donor to patients with HUS after bone marrow transplantation (BMT). This was very effective in ameliorating the hemolysis and increasing platelet numbers. We report here the successful use of an isosorbide in a patient with HUS after transplantation. Bone Marrow Transplantation (2000) 25, 109-110.
The objective was to evaluate the efficacy and safety of topically applied cream containing testosterone, isosorbide dinitrate and co-dergocrine mesylate compared to testosterone cream in the treatment of erectile dysfunction in aged men with low sexual interest. A randomised double-blind crossover trial was performed over two months. The subjects were 42 men with erectile dysfunction and low normal or slightly depressed testosterone level randomly allocated to two equal groups. Polypharmacy cream containing testosterone 0.8%, isosorbide dinitrate 0.5% and co-dergocrine mesylate 0.06% was applied for one month, and testosterone 0.8% cream for another month. The serum level of total testosterone was measured before and after each phase of treatment. Response to each therapy was assessed by a sexual questionnaire, measurement of tumescence and repeat penile duplex ultrasonography. Twenty-eight patients reported full erection and satisfactory intercourse with the polypharmacy cream. Thirteen men reported full erection and satisfactory intercourse with either cream. Polypharmacy cream increased penile arterial flow (P<0.001) and induced tumescence in 34 patients in lab. No patient in either phase of the study has tumescence or a significant increase in cavernous arterial peak systolic velocities after the application of testosterone cream. Serum level of total testosterone increased in all patients (P<0.05). Sexual desire was improved in 85% and 62% of patients during the treatment with polypharmacy cream and testosterone cream, respectively. No marked side effects were reported after either of them. Topical treatment with cream containing testosterone and vasoactive agents may represent a new effective treatment for erectile dysfunction associating with aging.
OBJECTIVE: The incidence of and risk factors for delayed adverse events (DAEs) that appear from 1 h to 7 days after injection of radiographic contrast media were investigated in patients who had undergone coronary angiography (CAG). METHODS: DAEs were monitored by questionnaire in 155 patients who received iomeprol. Isosorbide dinitrate was injected in every case. Risk factors for DAEs were analysed by a logistic regression model. RESULTS: Of 118 patients who returned questionnaires, 54 complained of DAEs, although no severe or fatal reactions occurred. Erythema, rash and nausea were frequent events. Female gender, total dose of isosorbide dinitrate <2 mg, and execution of acetylcholine provocation test were found to be the major risk factors, and the incidence of DAEs increased as the number of risk factors increased. CONCLUSION: Care should be taken when CAG is performed on female patients who undergo acetylcholine provocation tests and receive low-dose nitric oxide donor injections.
AIMS: Abnormal coronary vasomotion plays a role in the clinical expression of coronary artery disease. We hypothesized that the functional C825T polymorphism located in the ubiquitous G-protein beta3 subunit, implicated in the cellular signal transduction of many receptors, could modify artery coronary vasomotion. We assessed the potential association of the pertussis toxin-sensitive G protein beta3 subunit (GNB3) gene C825T polymorphism on coronary vasomotion in humans. METHODS AND RESULTS: We examined the response of angiographically normal human coronary arteries (n=131) after intravenous injection of methylergonovine maleate, a vasoconstrictor, followed by injection of isosorbide dinitrate, a vasodilator, according to GNB3 genotypes. Coronary vasomotion was assessed with quantitative coronary angiography. Subjects bearing at least one T allele had greater susceptibility to vasoconstriction in response to methylergonovine maleate than CC subjects, whereas vasodilation in response to isosorbide dinitrate did not differ among the different genotypes. CONCLUSION: The C825T polymorphism of the G-protein beta3 subunit may be a genetic determinant of coronary artery vasomotion in humans.
The report is based on a four-centre study on 25 patients with coronary insufficiency (ECG signs). In random sequence the following were given to each patient: a nitrate (isosorbide dinitrate), carbocromene, practolol, and oxyphedrine. The initial criterion for inclusion was S-T depression of 0.2 mV on stepwise exercise (bicycle ergometry). S-T depression, systolic blood pressure and heart rate changes were used as criteria. For each drug there was an acute test and a long-term test of 12 days. The Friedman test was used for the statistical evaluation of the results. Isosorbide dinitrate decreased the extent of S-T depression in the acute tests while practolol did so in the long-term test. Practolol reduced systolic pressure on long-term administration, with no difference in the acute experiment. Heart rate was reduced by practolol both acutely and long-term. These results give no indication for any possible differential treatment of coronary insufficiency, but this may be due to the selection of patients in this study.
BACKGROUND: It has been reported that renovascular hypertension activates the renin-angiotensin system, leading to an increase in oxidative stress. We sought to determine whether renal-artery angioplasty improves endothelial dysfunction in patients with renovascular hypertension through a reduction in oxidative stress. METHODS: We evaluated the response of forearm blood flow to acetylcholine, an endothelium-dependent vasodilator, and isosorbide dinitrate, an endothelium-independent vasodilator, before and after renal-artery angioplasty in 15 subjects with renovascular hypertension and 15 controls without hypertension who were matched for age and sex. Forearm blood flow was measured with the use of a mercury-filled Silastic strain-gauge plethysmograph. RESULTS: The forearm blood flow in response to acetylcholine was less in subjects with renovascular hypertension than in controls, although the forearm blood flow in response to isosorbide dinitrate was similar in the two groups. Angioplasty decreased systolic and diastolic blood pressures, forearm vascular resistance, and urinary excretion of 8-hydroxy-2'-deoxyguanosine and serum malondialdehyde-modified low-density lipoprotein (LDL), indexes of oxidative stress. After angioplasty, the mean (+/-SD) forearm blood flow in response to acetylcholine was increased in the patients with renovascular hypertension (19.3+/-6.8 vs. 29.6+/-7.1 ml per minute per 100 ml, P=0.002). The increase in the maximal forearm blood flow in response to acetylcholine correlated significantly with the decrease in urinary excretion of 8-hydroxy-2'-deoxyguanosine (r=-0.51, P=0.004) and serum malondialdehyde-modified LDL (r=-0.39, P=0.02). Coinfusion of ascorbic acid (vitamin C) augmented the response of forearm blood flow to acetylcholine before angioplasty (P<0.001) but not after angioplasty. CONCLUSIONS: These findings suggest that excessive oxidative stress is involved, at least in part, in impaired endothelium-dependent vasodilatation in patients with renovascular hypertension.
Underlying causes and precipitating causes of congestive heart failure (CHF) should be treated when possible. Older persons with CHF and normal left ventricular (LV) ejection fraction should have maintenance of sinus rhythm, treatment of hypertension and myocardial ischemia, slowing of the ventricular rate below 90 beats/minute, and reduction of salt overload. First-line drug treatment in the management of these persons is the use of loop diuretics combined with beta blockers as tolerated. Angiotensin-converting enzyme (ACE) inhibitors should be administered if CHF persists despite diuretics and beta blockers. If persons are unable to tolerate ACE inhibitors because of cough, rash, or altered taste sensation, angiotensin II type 1 receptor antagonists should be given. If CHF persists despite diuretics, beta blockers, and ACE inhibitors or the person is unable to tolerate beta blockers, ACE inhibitors, and angiotensin II type 1 receptor antagonists, isosorbide dinitrate plus hydralazine should be administered. Calcium channel blockers should be used if CHF persists despite administration of diuretics and the person is unable to tolerate beta blockers, ACE inhibitors, angiotensin II type 1 receptor antagonists, and isosorbide dinitrate plus hydralazine. Digoxin, beta blockers, verapamil, and diltiazem may be used to slow a rapid ventricular rate in persons with supraventricular tachyarrhythmias. Digoxin should not be used in persons with CHF in sinus rhythm with normal LV ejection fraction.
A 5-year-old girl at high risk for acute lymphoblastic leukemia was treated with high-dose chemotherapy and autologous peripheral blood stem cell transplantation (PBSCT). However, her condition was complicated by veno-occlusive disease of the liver (VOD) after PBSCT. For treatment of VOD, transdermal isosorbide tape was applied as a nitric oxide (NO) donor. The signs of VOD improved immediately after NO treatment was initiated, and the patient showed no side effects from the transdermal isosorbide tape.
Because of rapid tolerance development, the use of multiple daily doses of oral nitrates or continuous application of transdermal nitrate systems can no longer be considered justified. Only with an interval treatment, which prevents nitrate accumulation in the plasma such that, from low baseline values, renewed administration of the drug results in a marked increase in plasma concentration, is it possible to utilize the antianginal and antiischaemic effects of nitrates for meaningful long-term treatment. For isosorbide dinitrate and isosorbide 5-mononitrate, as well as for transdermal nitroglycerin systems, interval treatment dosing regimens with maintained effectiveness documented in controlled studies have been delineated. To some degree, the principle of interval treatment can be achieved with continuously applied transdermal patches designed for discontinuous release of their content, which yield maintained though somewhat attenuated effects. Recent studies have shown that the tolerance to nitroglycerin, which develops within the first 12h of contact with currently available transdermal patches, can be prevented by gradually increasing the plasma concentration during this period of time. Evidence for clinically relevant rebound phenomena during interval treatment has not been observed.
The present study summarizes recent investigations in our laboratory, demonstrating that a number of organic nitrates, including glyceryltrinitrate, isosorbide dinitrate, isosorbide-2-mononitrate and the novel nitrate teopranitol stimulate the release of a prostacyclin (PGI2)-like antiplatelet activity from isolated bovine coronary arteries and veins. In bioassay experiments this increase amounted to 50 to 200% of control. Evidence for nitrate induced PGI2 stimulation is presented by inhibition of its formation by indomethacin and dexamethasone, the demonstration of inhibition of thrombin induced thromboxane generation of washed platelet suspensions by nitrate stimulated vessel incubates and an enhanced accumulation of the hydrolysis product of PGI2, 6-oxo-PGF1 alpha, in incubates of teopranitol stimulated vessels. This action is obtained at nanomolar, i.e. therapeutic concentrations of the compounds and requires the presence of free nitro group(s) at [exo] position of the isohexide molecule. There was no correlation between PGI2 release and the relaxing action of the nitrates on isolated vessel strips. The inhibitor of cyclic GMP accumulation, methylene-blue, also blocked the generation of the antiplatelet activity by glyceryltrinitrate and teopranitol. Recent evidence suggests that cGMP accumulation via intermediate nitrogen oxide (NO) production mediates the vascular effects of organic nitrates. Since NO is also a potent antiplatelet agent, it is concluded that a nitrate stimulated PGI2 release associated with or mediated by NO formation might explain the antiplatelet actions of organic nitrates in vitro and ex vivo.
To address the issues of tolerance development and its circumvention during long-term treatment with nitrates, several controlled studies have been performed. In patients with coronary artery disease, during long-term treatment with isosorbide dinitrate (ISDN) in sustained-release form at dosages of 20 mg t.i.d., 40 mg t.i.d. and 60 mg t.i.d., both the rate of anginal attacks and the ischaemic reaction to exercise were unaffected. After a marked acute anti-ischaemic effect to 40 mg ISDN in nonsustained-release form, during chronic administration of the same dose four times daily, in association with continuously-high nitrate plasma concentrations, similarly, there were no significant effects. On use of nitroglycerin (NTG) transdermal patches delivering 10 mg, 15 mg and 30 mg per 24 hours, respectively, renewed patch application after 24 hours was not met with the same marked response observed after initial application. Clearly attenuated effects could be seen within 8 to 12 hours. These results show that tolerance development is incurred when the incrementation in plasma concentration after a repeated nitrate dose is of relatively limited magnitude with respect to baseline values. The observation of rapid reversibility of nitrate tolerance lead to the concept of interval treatment which on daily use incorporates a sufficiently long period without nitrate administration. On use of a nitrate-free treatment interval employing a regimen of 20 mg ISDN nonsustained-release form twice daily in the morning and at midday, 120 mg ISDN sustained-release form once daily or 50 or 100 mg isosorbide 5-mononitrate once daily, maintained effectiveness has been documented, as it has also been shown for treatment with NTG patches delivering 10 mg per 24 hours on incorporation of a 12-hour patch-free interval. The currently available patch system with discontinuous NTG delivery does not incur a complete loss of action but a considerable attenuation of its effects indicates the need for further refinements. Thus interval treatment guarantees maintenance of nitrate effects, albeit with the limitation that 24-hour therapeutic coverage is not enabled.
Nitric oxide (NO) donors are capable of ripening the human cervix during pregnancy. The purpose of this study was to examine how NO donors may be involved in this process. Cervical biopsies were obtained from pregnant women randomized to receive isosorbide mononitrate (n = 10) or no treatment (n = 10) prior to suction termination. Enzyme-linked immunosorbent assays (ELISA) were performed on culture supernatant for interleukin (IL)-1, IL-6, IL-8, IL-10, IL-15, tumour necrosis factor-alpha, monocyte chemoattractant protein-1 and prostaglandin metabolites. Immunohistochemistry was performed to localize these cytokines, cyclooxygenase (COX)-1, COX-2 and prostaglandin dehydrogenase in cervical tissue and reverse transcription-polymerase chain reaction (RT-PCR) to identify COX-1 and COX-2 expression. Biopsies treated with the NO donor isosorbide mononitrate (IMN) produced significantly greater amounts of prostaglandin F(2alpha) in culture and lower amounts of thromboxane B(2) than controls (572.8 versus 34.9 pg/ml, P < 0.05; 53.3 pg/ml versus 530.9 pg/ml, P < 0.01 respectively). The release of other prostaglandins and of cytokines was not affected by treatment with NO. Inflammatory mediators were localized to cervical tissue and COX-1 and COX-2 expression was confirmed by RT-PCR. In conclusion, the mechanism of NO donor-induced cervical ripening during pregnancy may be mediated in part via increased prostaglandin F(2alpha) synthesis.