Effect of verapamil on left ventricular function: A randomized,placebo-controlled study

Verapamil has a negative inotropic action in isolated cardiac muscle. Its effects on left ventricular function were tested in 25 patients with suspected coronary artery disease. A double-blind, randomized, placebo-controlled study design was used. Verapamil (0.2 mg/kg over 10 minutes) significantly lowered mean arterial pressure (from 105 to 89 mm Hg) while increasing the cardiac index (from 2.8 to 3.1 liters/min/m²). No statistically significant effect was seen on heart rate, left ventricular end-diastolic pressure or end-systolic volume index, ejection fraction, peak rates of systolic wall thickening or diastolic wall thinning, or percentage of hemiaxial shortening. However, there was a small increase in the left ventricular end-diastolic volume index (from 94 to 102 ml/m²). Important findings were a reduction in systemic vascular resistance (from 39 to 30 U·m²), an increase in left ventricular end-diastolic volume index consistent with a negative inotropic effect, and no evidence of improved regional wall dynamics in portions of the left ventricular wall considered hypokinetic because of myocardial ischemia.     

Right and left ventricular function after the Mustard procedure in transposition of the great arteries.

Right and left ventricular function was assessed at cardiac catheterization in 33 asymptomatic patients 0.5 to 11 years (mean 4.6) after the Mustard operation for complete transposition of the great arteries. Ages at operation had ranged from 0.5 to 16 years (mean 4.2 years). Right ventricular function was assessed using videodensitometric determination of ejection fraction and ventricular volume data. Ventricular volumes were obtained by computerized video analysis utilizing Simpson's rule. The right ventricular ejection fraction was 37 +/- 11 percent (standard deviation), as assessed with videodensitometry and 42 +/- 10 percent as assessed with ventricular volume--both values less than normal (P less than 0.001). Right ventricular end-diastolic volume was significantly greater than normal (P less than 0.001) and averaged 202 +/- 70 percent, but left ventricular end-diastolic volume averaged only 125 +/- 53 percent. These observations after the Mustard operation indicate that right ventricular function is seriously decreased with relatively preserved left ventricular function. They support efforts for surgical correction utilizing the left ventricle as the systemic ventricle.     

Trial of combined warfarin plus dipyridamole or aspirin therapy in prosthetic heart valve replacement: danger of aspirin compared with dipyridamole

Despite the use of oral anticoagulation in patients with prosthetic heart valves, persistent thromboembolism over time warrants a search for improved methods of prevention. Thus, patients receiving 1 or more mechanical prosthetic heart valves were randomized to therapy with warfarin plus dipyridamole (400 mg/day) or warfarin plus aspirin (500 mg/day) on the basis of location and type of valve and surgeon, and followed up with a concurrent, nonrandomized control group taking warfarin alone. In 534 patients followed up 1,319 patient-years, excessive bleeding (necessitating blood transfusion or hospitalization) was noted in the warfarin plus aspirin group (23 of 170 [14%], or 6.0/100 patient-years) compared with warfarin plus dipyridamole (7 of 181 [4%], or 1.6/100 patient-years, p less than 0.001), or warfarin alone (9 of 183 [5%], or 1.8/100 patient-years, p less than 0.001). A trend was evident toward a reduction in thromboembolism in the warfarin plus dipyridamole group (2 of 181 [1%], or 0.5/100 patient-years) as compared with warfarin plus aspirin (7 of 170 [4%], or 1.8/100 patient-years), or warfarin alone (6 of 183 [4%], or 1.2/100 patient-years). Adequacy of anticoagulation (based on 12,720 prothrombin time determinations) was similar in all 3 groups with 65% of prothrombin times in the therapeutic range (1.5 less than or equal to prothrombin time/control less than or equal to 2.5), 30% too low, and 5% too high. Warfarin plus aspirin therapy resulted in excessive bleeding and is contraindicated. Longer follow-up study is needed to determine whether further separation of the incidence of thromboembolism can be detected.     

Idiopathic dilated cardiomyopathy in the young: clinical profile and natural history

The clinical profile and course of documented cases of idiopathic dilated cardiomyopathy in children have been poorly characterized. Twenty-four patients (median age 2 years, range less than 1 month to 18 years) with idiopathic dilated cardiomyopathy were identified from Mayo Clinic records from 1973 to 1982. The most common presentation was congestive heart failure (92% of patients). Echocardiography (22 patients) generally revealed a dilated left ventricle with reduced fractional shortening (mean 14%) and ejection fraction (mean 26%). Two-dimensional echocardiographic evidence of left ventricular thrombus was present in 3 (23%) of 13 patients. Median cardiac index and left ventricular end-diastolic pressure (19 patients) were 2.5 liters/min per m2 and 22 mm Hg, respectively. Myocardial biopsy in eight patients showed nonspecific findings without active inflammation or evidence of endocardial fibroelastosis. On follow-up (mean duration 33 months, range 0 to 149), systemic arterial embolism had occurred in 2 (8%) of 24 patients. Fifteen of 24 patients had died (63% survival at 1 year and 34% survival at 5 years of follow-up). The cause of death was congestive heart failure in 11, complications after cardiac transplantation in 3 and sudden cardiac death in 1. Nine patients are alive at a mean follow-up time of 65 months (range 26 to 149); five are asymptomatic. Serial determination of left ventricular systolic function, available in all survivors, showed improvement in six patients and no significant change in three. Severe mitral insufficiency was present only in patients who ultimately died. A recent viral syndrome was noted more frequently in patients who survived.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hemodynamic spectrum of “dominant” right ventricular infarction in 19 patients

In 19 patients right ventricular infarction was diagnosed on the basis of electrocardiographic features of acute inferior infarction and clinical evidence of elevation of systemic venous pressure and an absence of pulmonary congestion. Right heart catheterization documented elevated right ventricular end-diastolic pressure (mean 15.5 mm Hg) and commensurate right atrial pressure (mean 14.9 mm Hg). In all patients the pulmonary capillary wedge pressure (mean 13.2 mm Hg) was exceeded or equaled by the right ventricular end-diastolic pressure, suggesting a disproportionate reduction in right ventricular compliance or contractile function, or both. Thirteen patients were hypotensive (systolic blood pressure less than 100 mm Hg on admission), including six patients with cardiogenic shock.

Right ventricular infarction is an uncommon and potentially reversible cause of cardiogenic shock;yet, in the experimental model, isolated right ventricular damage is relatively well tolerated. To identify the factors associated with systemic hypotension, data from patients with and without compromised systemic hemodynamic function were compared. In hypotensive patients, the right ventricular end-diastolic pressure was significantly higher (16.8 versus 12.8 mm Hg;p < 0.01) and reflected more extensive right ventricular damage. A pulmonary wedge pressure of 15 mm Hg or more was noted only among the hypotensive patients, and their wedge pressure (mean 14.8 mm Hg) was significantly greater than that of normotensive patients (mean 9.7 mm Hg, p < 0.05). Therefore, in patients with right ventricular infarction, an additional impairment of left ventricular function due to associated infarction of the inferior left ventricle is a significant factor causing hypotension. The elevated wedge pressure may influence right ventricular output by affecting pulmonary arterial diastolic pressure and right ventricular afterload. Right ventricular peak systolic pressure as an index of right ventricular afterload was significantly higher in hypotensive than in normotensive patients (30.5 versus 23.8 mm Hg, p < 0.03), and there was a linear correlation between this pressure and the pulmonary capillary wedge pressure (r = 0.895, p < 0.001).

There was one hospital death (mortality rate 5.3 percent). Clinical management generally consisted of administration of fluids and digitalis and implantation of a temporary pacemaker. This study emphasizes the relatively favorable prognosis of this condition and suggests that aggressive diagnosis and management are appropriate.     

Systemic embolism in chronic left ventricular aneurysm: incidence and the role of anticoagulation

The incidence and prevention of systemic embolism in patients with chronic left ventricular aneurysm have been controversial. This retrospective study investigated the incidence of clinically evident embolic events and the effect of oral anticoagulation in patients with unequivocal angiographically defined left ventricular aneurysm. Between 1971 and 1979, 76 patients met the ventriculographic criteria and received initial medical management. The median interval from myocardial infarction to ventriculography was 11 months (range 1 month to 16 years) and subsequent median follow-up time was 5 years. Twenty patients receiving anticoagulant therapy were followed up for a total of 40 patient-years and 69 patients not on anticoagulant therapy were followed up for a total of 288 patient-years; 13 patients were included in both subsets. Twenty-eight patients died during follow-up and the 3 and 5 year survival rates were 75 and 61%, respectively. Only one patient not receiving anticoagulant therapy had a clinical embolic event, resulting in an incidence of 0.35 per 100 patient-years. Therefore, in the absence of other predisposing conditions, the extremely low incidence of systemic emboli in these patients with chronic (first documented at least 1 month after myocardial infarction) left ventricular aneurysm does not justify the use of long-term oral anticoagulant therapy.     

Ventricular arrhythmias during coronary angiography in patients with angina pectoris or chest pain syndromes

Of 7,915 patients undergoing coronary angiography from 1978 to 1983, 39 (25 men and 14 women with a mean age of 57 years [range 37 to 79]) had sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) during the procedure. Nine patients had atypical chest pain and 30 had typical angina. Fifteen had had a previous myocardial infarction. One patient had a history of VT or VF. Electrocardiograms taken at rest revealed a prolonged QT interval in 14. A normal ejection fraction was found in 79%. Coronary angiography revealed that 10 patients had 3-vessel disease, 15 had 1- or 2-vessel disease and 14 had normal coronary arteries. The VT or VF was seen with injection of contrast medium into the right coronary artery in 24, the left coronary artery in 10 and vein bypass grafts in 5 patients. Of the episodes of VT or VF, 67% occurred after injection of contrast medium into a minimally diseased coronary artery. In patients in whom VT or VF occurred after injection into a minimally diseased coronary artery, the arrhythmia was preceded by bradycardia, usually with pronounced widening of the QRS and QT intervals. This response was significantly different from that in patients in whom VT or VF occurred after injection into a coronary artery with significant stenosis; in these patients, VT or VF was initiated by a single premature ventricular contraction on a T wave. VT or VF was successfully cardioverted in all instances, without further arrhythmias.     

Angiographic occurrence and clinical correlates of intraluminal coronary artery thrombus: role of unstable angina

The importance of intraluminal coronary artery thrombus in acute myocardial infarction is now recognized. Coronary thrombi, however, may be important in ischemic syndromes other than infarction. The coronary angiograms of 268 consecutive patients undergoing diagnostic angiography were prospectively examined for intracoronary thrombus and form the basis of this study. Of these patients, 29 (11%) (25 men and 4 women) met the criteria for coronary artery thrombus. Of the 29 patients with thrombus, 24 (83%) had unstable angina before angiography. The five remaining patients with thrombus had had a transmural myocardial infarction 3 to 18 months before cardiac catheterization. In 21 patients, the thrombus was distal to a significant stenosis; in 8 it was proximal to or at the site of a significant stenosis. Coronary artery thrombus was identified in 24 (35%) of 67 patients with unstable angina compared with only 5 (2.5%) of 201 patients with stable angina (p less than 0.0001).     

Two-dimensional echocardiographic assessment of dextrocardia: A segmental approach

Two-dimensional echocardiography was used in the prospective evaluation of 40 patients with the clinical diagnosis of dextrocardia. A segmental analysis of the situs, connections, ventricular anatomy, and chamber positions was utilized for a complete diagnostic assessment. An adequate examination was possible in 33 of these patients; the findings were confirmed by cardiac catheterization and angiography in 31 patients and at operation in 26.

Use of the location of the liver and the drainage of the hepatic veins and inferior vena cava allowed atrial visceral situs to be defined in 33 patients (solitus 21, inversus 9, and ambiguous 3). Pulmonary venous connections were correctly identified in 27. In 33 patients, atrioventricular (AV) and ventriculoarterial connections and ventricular anatomy were correctly predicted. Twenty patients had 2 separate well-developed ventricles. Ventriculoarterial connections were determined correctly in all 20 patients: concordant in 5, discordant in 6, double-outlet right ventricle in 5, and single-outlet right ventricle (pulmonary atresia) in 4. In 16 patients a ventricular septal defect was correctly identified. In the remainder the ventricular septum was intact.

Thirteen patients had univentricular heart: 8 had 2 AV valves (double-inlet ventricle), 3 had common AV inlet, and 2 had atresia of 1 AV connection.

Two-dimensional echocardiography allowed the accurate assessment of complex congenital heart defects associated with dextrocardia. Utilizing a segmental approach, one can correctly predict atrial-visceral situs, ventricular morphology and situs, and AV and ventriculoarterial connections.     

Hypertrophic obstructive cardiomyopathy: Ten- to 21-year follow-up after partial septal myectomy

This study reviews the outcome in 36 consecutive patients who survived partial septal myectomy for hypertrophic obstructive cardiomyopathy operated on between 1960 and 1972. All patients were followed up until death or until June 1981 (mean 13.4 years). Of the 26 survivors, 17 had been more than mildly symptomatic preoperatively, but only 1 remained so postoperatively. The operation was effective in relieving the obstruction (peak systolic pressure gradient reduced from 79 to 8 mm Hg [p< 0.001), and mitral regurgitation was relieved. No survivor's symptoms worsened, but 10 died late—4 suddenly, 5 from congestive heart failure, and 1 from a malignancy. The 10-year survival rate was 77%. No correlation with outcome was found with respect to age, surgical approach, preoperative functional class, pressure gradient, left ventricular end-diastolic pressure, or presence of atrial fibrillation, but atrial fibrillation occurring late postoperatively (12 patients) was associated with an increased frequency of late death (7 of 10 late deaths) or continuing New York Heart Association functional class III status. Early or late postoperative complete heart block occurred in 1 patient each. Thus, these results suggest a favorable effect of operation and support continued surgical intervention for appropriate patients.     

Hypertrophic obstructive cardiomyopathy and lentiginosis: A little known neural ectodermal syndrome

Eleven patients, 10 male, with classic hypertrophic obstructive cardiomyopathy and lentiginosis are described. Physical examination showed differences from the few previously reported cases in that (1) this condition was not confined to children; (2) mental retardation, sensorineural deafness and gonadal and somatic infantilism were either rare or absent; and (3) detailed family studies provided no evidence that this condition was inherited. Nine patients underwent cardiac catheterization and left ventricular angiography; all had left ventricular outflow obstruction and three had concomitant right ventricular outflow obstruction with a pressure gradient in excess of 100 mm Hg. Ten of the 11 patients were severely symptomatic, and 7, each with a left ventricular pressure gradient of more than 70 mm Hg, underwent successful septal myotomy/myectomy that resulted in marked symptomatic improvement that was maintained after long-term follow-up.     

Results of the modified Fontan operation for congenital heart lesions in patients without preoperative sinus rhythm

Preoperative sinus rhythm has been a criterion for the Fontan operation. However, of 297 patients who underwent the Fontan operation between October 1973 and February 1984, 12 (4%) did not have sinus rhythm. The age at operation ranged from 4 to 34 years (median 15). Nine patients had a univentricular heart, two had tricuspid atresia and one had a complex form of transposition. In all 12 patients, 3 to 8 of the 10 proposed criteria for operability were not met. An atrioventricular (AV) conduction abnormality was present in seven patients, six with complete AV block and one with AV dissociation. The patient with complex transposition had complete AV block and atrial fibrillation. Postoperatively, all seven patients continued to have an AV conduction abnormality, and those with complete AV block had a permanent pacemaker implanted. Six of the 12 study patients had atrial flutter or fibrillation refractory to antiarrhythmic medications. Postoperatively, four of the six patients had sinus rhythm. Two of the six patients had complete AV block (including the patient with complex transposition) and both had a permanent pacemaker implanted. Three of the 12 patients died (mortality rate 25%). The nine survivors were followed up for 6 to 55 months; no late deaths occurred. All had marked clinical improvement. This study demonstrates that 1) complete AV block is not a contraindication to the Fontan operation, 2) some patients may not require AV synchrony postoperatively for survival, and 3) postoperative atrial flutter or fibrillation may cease or be easier to control after the Fontan operation.     

Effects of serotonin and histamine on proximal and distal coronary vasculature in dogs: Comparison with alpha-adrenergic stimulation

The effect of several vasoactive agents on epicardial conductance arteries and distal resistance arteries was studied in intact dogs using a special catheter system to infuse vasoactive mediators directly into the left anterior descending coronary artery of intact dogs. Serotonin produced significant epicardial vasoconstriction (42% cross-sectional area reduction, p <0.01), whereas histamine had no effect on proximal coronary arteries. Phenylephrine, an alpha-adrenergic agonist, produced an 11% reduction in cross-sectional area. Distal coronary vascular resistance (pressure/flow) changes were small for serotonin and phenylephrine, whereas histamine significantly dilated the peripheral vascular bed and caused flow measured by xenon-133 washout to increase from 30.4 ± 4.0 to 72.4 ± 12.6 ml/min • 100 g (p <0.05). These results show that vasoactive mediators can have different actions on coronary resistance and conductance vessels. Serotonin is a potent vasoconstrictor of epicardial coronary arteries but does not produce significant constriction of coronary resistance vessels.     

Pulmonary blood supply in patients with pulmonary atresia and ventricular septal defect

The heart and lung specimens in 31 cases of pulmonary value atresia and ventricular septal defect were studied at autopsy. Three types of natural arterial blood supply to the lungs were identified: 1) ductus arteriosus (patient or ligamentous) (12 cases); 2) major collateral arteries (20 cases); and 3) diffuse small pleural arterial plexus coexisting with either ductus arteriosus or major collateral arteries (17 cases). The ductus arteriosus and major collateral arteries did not coexist in the same lung in these cases. Confluent central pulmonary arteries were present in 22 (71%) of the 31 cases, involving 7 (58%) of the 12 cases of ductus arteriosus, 14 (70%) of the 20 cases with major collateral arteries and 1 case with an aorticopulmonary window. The pulmonary trunk (atretic or patent) was identifiable in 24 (77%) of the 31 cases. A lung or lungs that connected to a ductus (or ligamentum) had a complete and unifocal intrapulmonary arterial distribution (without arborization abnormalities). Major collateral blood supply was frequently multifocal and associated with arborization abnormalities. The size of the central pulmonary arteries was not related to the type of arterial blood source but seemed to be related to the amount of blood flow actually reaching the vessels, This study demonstrated a complex systemic arterial system supplying the lungs in these cases. The size, sources and relation among the ductus, the pulmonary artery confluence, the large and small collateral vessels and the intrapulmonary system are far more varied than has ever been reported previously. Careful and thorough premortem studies are crucial if surgical intervention is contemplated.     

Role of two-dimensional echocardiography in the prediction of in-hospital complications after acute myocardial infarction

To evaluate prospectively the prognostic value of two-dimensional echocardiography after acute myocardial infarction, two-dimensional echocardiography was performed on 61 consecutive patients who were admitted to the hospital with this condition. A left ventricular wall motion score index was derived from analysis of regional wall motion; an index of 2.0 or more within 12 hours of admission identified patients at high risk for pump failure, malignant ventricular arrhythmia or death. These complications occurred in 24 of 27 patients with an initial wall motion score index of 2.0 or more, but in only 6 of 34 with an initial index of less than 2.0 (p less than 0.0005). Of the 47 patients who were in Killip class I on admission, complications developed in 11 (79%) of the 14 with an initial index of 2.0 or more, but in only 6 (18%) of the 33 with an initial index of less than 2.0. After acute myocardial infarction, early determination of the wall motion score index by two-dimensional echocardiography is useful for identifying patients at high risk for complications and is especially valuable in the subset of patients who initially seem to be in stable condition as judged from clinical variables.     

Late results after extracardiac conduit repair for congenital cardiac defects

Analysis of the late results in 352 patients surviving insertion of an extracardiac conduit before mid 1977 has provided a mean follow-up interval of 65 months. Three fourths of the patients remain in improved condition after operation. Serial measurements of transconduit gradient are available In 90. The median change was +7 mm Hg and the mean +21 mm Hg. Reoperation was required in 16 percent of patients (mortality rate 9 percent), most commonly (77 percent) because of progressive conduit stenosis, more commonly for transposition of the great arteries than for other types of anomalies, and more commonly after use of a homograft aortic conduit than a Hancock conduit. The side of the aorta on which the conduit was placed exerted no significant influence. The postrepair transconduit gradient did not affect the need for reoperation. Late survival was 95 percent at 1 year, 85 percent at 5 years, and 73 percent at 10 years and was significantly better (probability [p] < 0.006) for patients with pulmonary atresia than for the others. The hospital mortality rate was highest, and the late mortality rate lowest, for children less than 5 years of age; the overall survival rate in this age group was lower. The postrepair right ventricular to left ventricular pressure ratio, together with age, was a principal prognostic indicator of late survival, being less good when more than 0.73. The most frequent causes of late death were progressive congestive heart failure and sudden death.     

Valve ring abscess in infective endocarditis: Visualization with wide angle two dimensional echocardiography

Two dimensional echocardiography permitted visualization of a valve ring abscess complicating infective endocarditis in four patients. Abscess formation was defined as an echo-free cavity within tissues surrounding the infected valve. Abscess in the valve ring extended into the perivalvular structures, including the upper ventricular septum (one patient), left ventricular myocardium (one patient) and contiguous fibrous structures (three patients). Two dimensional echocardiography is the only noninvasive technique for direct visualization of the abscess cavity complicating infective endocarditis and may allow better appreciation of incidence, evolution and natural (or unnatural) course of this heretofore seldom recognized complication of infective endocarditis.     

Transient atrioventricular block after open-heart surgery for congenital heart disease

The records of 22 patients with transient atrioventricular (AV) block after open-heart surgery for congenital heart disease from 1972 to 1978 were reviewed to determine the natural history of this entity. Preoperatively, no patient had AV block; 3 had right bundle branch block (BBB), 1 had left BBB and 5 had nonspecific intraventricular conduction delay. Complete AV block developed in 20 patients and Mobitz II AV block in 2. Transient AV block occurred intraoperatively in 14 patients and within 48 hours postoperatively in 8; AV block persisted for greater than or equal to 48 hours postoperatively in all patients, for a mean of 7.3 days (range 2 to 28). During a follow-up of 5.5 years (range 2.5 to 10), late AV block developed in 2 patients. None of the 18 patients whose escape QRS complex morphology during AV block was similar to the final QRS complex during normal sinus rhythm or atrial fibrillation with AV conduction had late AV block, whereas 2 of the 4 in whom it differed did (p less than 0.01). There was no difference in the escape rate between the 2 groups. Thus, late development of high-grade AV block is infrequent among patients with transient postoperative AV block. An escape QRS complex during postoperative AV block that differs from the QRS complex seen on recovery of normal sinus rhythm or atrial fibrillation with anterograde conduction may identify those at high risk of late AV block.     

Echocardiographic features of carcinoid heart disease

We reviewed the records of the Mayo Clinic patients with known carcinoid syndrome in whom echocardiographic studies had been done. Nineteen patients had M-mode and 2-dimensional echocardiographic examinations, and 1 patient had an M-mode examination only. Of the 20 patients, 8 had no evidence by echocardiogram of carcinoid heart disease; 2 had changes in the tricuspid valve echogram suggestive of early carcinoid heart disease, and the other 10 patients had the following distinctive echocardiographic findings: (1) the pattern of right ventricular volume overload (enlarged right ventricle with abnormal septal motion); (2) abnormal right-sided valves, including (a) a striking appearance of the tricuspid valve, the leaflets appearing thickened, retracted, and fixed in a semiopen position throughout the cardiac cycle, and (b) thickened, retracted pulmonic valve cusps, when visualized; and (3) the left-sided valves and chambers rarely involved. These echocardiographic features are distinctive of advanced carcinoid heart disease and correlate closely with pathologic findings.