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Unilateral absence of a pulmonary artery is a rare congenital malformation. This report details the finding in two cases of this anomaly associated with peripheral stenosis of the contralateral pulmonary artery.

Nineteen adolescent or adult patients with secundum atrial septal defect (ASD) underwent pulmonary arteriography to evaluate the presence of proximal pulmonary arterial (PA) thrombosis. This procedure demonstrated proximal PA thrombosis in 8 patients (group 2). These patients had a distinctive hemodynamic profile, consisting primarily of significant PA hypertension. None of the 11 patients with normal angiograms (group 1) had severe PA hypertension (p less than 0.0001). Proximal PA thrombosis appears to be the major factor in the development and progression of PA hypertension in adult patients with ostium secundum ASD. Pulmonary angiography should be undertaken in all adult patients with ostium secundum ASD who have at least moderate PA hypertension. Long-term anticoagulation is advocated for patients with PA thrombosis irrespective of a decision for surgical intervention.

Left ventricular hypertrophy due to diastolic overload is characterized by the following in lead V6: (a) tall R wave; (b) prominent initial Q wave; (c) minimally elevated concave-upward ST segment; and (d) relatively tall symmetrical T wave. Reciprocal deep S waves are seen in lead V1. This study reflects a further evaluation of these parameters in the four main causes of left ventricular diastolic overload: mitral incompetence, aortic incompetence, patent ductus arteriosus, and ventricular septal defect. An S wave in lead V1 which is equal to or greater than the R wave in lead V6 excludes the diagnosis of mitral incompetence.

In 1873 Kussmaul 1 reported the observation that, in 2 patients with constrictive pericarditis, the expected inspiratory collapse of neck veins was replaced by increased inspiratory distension. The association of Kussmaul's sign, as it subsequently became called, with constrictive pericarditis is now widely accepted. At the same time it is also recognized that it is not specific to this pathology and can be observed in congestive heart failure, 2–4 restrictive cardiomyopathy, 5 right ventricular infarction 6 and acute cor pulmonale. 7 As stressed by Spodick, 8 it is not a feature of pericardial tamponade and is of value in distinguishing tamponade from pericardial constriction. In spite of its clinical value and wide use, the underlying mechanism is poorly understood. 9 We report our observations based on 6 patients with chronic constrictive pericarditis in an attempt to clarify the mechanism of this sign.

Eleven patients with implanted pervenous pacemakers were found to have unusual QRS morphology resembling right bundle branch block (RBBB) on the 12-lead electrocardiogram. In nine patients, the tip of the electrode catheter was established with certainty to be in the right ventricular apex. In eight of the nine, the standard leads showed a left bundle branch block pattern (LBBB), whereas only the precordial leads V 1 and V 2 resembled RBBB. In only one of the nine was the RBBB pattern also seen in the standard leads. In all nine, recording the precordial leads one intercostal space below the usual space eliminated the RBBB pattern in V 1 -V 2 and resulted in inscription of a QS complex, whereas recording the leads one space higher than usual enhanced the height of the R wave. This is explained by the marked superior and slight anterior orientation of the main QRS complex in right ventricular pacing. It is suggested that the pattern of RBBB in V 1 -V 2 +LBBB in lead 1 be named pseudo RBBB pattern since it does not represent left prior to right ventricular activation.

The timing of surgery in patients with severe aortic regurgitation and left ventricular (LV) failure, particularly when associated with active infective endocarditis (IE), is of the utmost importance. From July 1982 to May 1984, 34 patients, aged 15 to 60 years, with severe aortic regurgitation underwent immediate (within 24 hours of diagnosis) aortic valve surgery. All patients were in New York Heart Association class IV for LV failure. Eighteen patients had right-sided heart failure. Decision for immediate surgery was based on the echocardiographic demonstration of diastolic closure of the mitral valve or of vegetations on the aortic valve. Premature closure of the mitral valve was demonstrated echocardiographically in 17 patients, 13 of whom had diastolic crossover of LV and left atrial pressure tracings recorded at surgery. IE of the aortic valve was confirmed at surgery in 29 patients, 27 of whom had vegetations on echocardiography. Seven patients required replacement of both aortic and mitral valves. Antibiotic therapy for IE was started immediately after blood cultures were taken and continued for 4 to 6 weeks postoperatively. The mortality rate within 30 days of surgery was 6% for the group as a whole and 7% for those with IE. Mean follow-up period for the 32 survivors was 10.6 months. There were 2 late deaths. No patient had periprosthetic regurgitation or persistence of endocarditis. Procrastination in referral for surgery of these extremely ill patients is not justified and is likely to be associated with higher risks of morbidity and mortality.

The mechanism of severe mitral regurgitation (MR) due to active rheumatic carditis is ill defined. This study involved 73 patients, aged 7 to 27 years (mean 13), with severe MR and active rheumatic carditis who were subjected to surgery. Sixty-one were studied retrospectively (group 1) and 12 prospectively (group 2). Active rheumatic carditis was diagnosed according to the modified Jones' criteria, morphologic appearances of the heart at operation and histology of the valve. All patients had preoperative 2-dimensional echocardiographic and intraoperative assessment of the mitral valve apparatus. The presence of mitral valve prolapse--defined as failure of leaflet edge coaptation resulting in systolic displacement of the free edge of the involved leaflet toward the left atrium--was determined in all patients. Mitral anular diameter and maximal systolic chordal length were measured at 2-dimensional echocardiography in group 2 patients and compared to values obtained from matched control subjects. Anular and chordal dimensions in 6 of the group 2 patients were correlated with precise measurements obtained at surgery. Mitral valve prolapse involving the anterior leaflet was detected on echocardiography and confirmed at surgery in 69 patients (94%). Mitral anular dilatation was observed at operation in 70 patients (96%). Maximal anular diameter was significantly greater (p less than 0.0001) than in matched control subjects (37 +/- 4 vs 23 +/- 2 mm). The mean anular dimension measured at surgery (36 +/- 3 mm) was similar to that obtained by echocardiography and individual values using the 2 methods correlated well (r = 0.93). Chordal elongation was observed in 66 patients at operation (90%).(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise capacity is frequently impaired in patients with mitral stenosis (MS) and sinus rhythm (SR). The resulting increased heart rate, which shortens the diastolic filling period, and the increased cardiac output lead to further elevations of left atrial pressure and subsequent pulmonary congestion. The effect of the β-receptor blocking agent atenolol, 100 mg/day, was assessed in 13 patients with MS and SR. Exercise performance was assessed using a modified multistage Bruce protocol after 2 weeks of placebo and after 2 weeks therapy with atenolol in a single-blind, crossover, placebo-controlled, randomized study. Atenolol resulted in significant decreases in mean heart rates at rest and during exercise (p = 0.0015) and a significant increase in total exercise time (p = 0.0015). Maximal exercise capacity was also significantly improved (p = 0.0015). All patients were both objectively and subjectively improved by atenolol. Thus, β-blockade with atenolol improves exercise capacity in patients with MS and SR and may be of benefit to most such patients. The improved effort tolerance is attributed to reduction of the exercise-associated sinus tachycardia by β-blockade, allowing a longer diastolic filling period and better left atrial decompression.

Summary This paper reflects a hitherto undescribed mechanism for alternation of conduction time during supraventricular reciprocating tachycardia. Delayed anterograde conduction through an A-V nodal pathway effectively delays conduction of the reciprocal impulse to its retrograde course and hence to its intrajunctional reciprocal point: the point where it begins anterograde conduction once again. This section of the A-V nodal pathway consequently has a longer recovery time. The ensuing anterograde conduction is therefore faster and the ensuing cycle therefore shorter. The shorter ensuing cycle, in turn, means that the returning impulse reaches its intrajunctional reciprocal point earlier. There is consequently less time for recovery for the anterograde A-V nodal pathway. Hence the ensuing delay and longer cycle. This establishes a sequel of long and short cycles due to alternation of conduction.

Objectives The purpose of this research was to evaluate the therapeutic value of initiating a beta-blocker before an angiotensin-converting enzyme inhibitor (ACEI) in the treatment of heart failure. Background Although ACEI and carvedilol produce benefits in heart failure, whether the order of initiation of therapy determines the impact on left ventricular (LV) function and New York Heart Association functional class (NYHA FC) has not been determined. Methods A single-center, prospective, randomized, open-label study was performed. We evaluated whether initiation of therapy with carvedilol either before (n = 38) or after (n = 40) perindopril therapy in newly diagnosed patients in NYHA FC II to III heart failure with idiopathic dilated cardiomyopathy, with the addition of the alternative agent after six months, determined subsequent changes in NYHA FC and LV function (echocardiography and radionuclide ventriculography). Study drugs were titrated to maximum tolerable doses. Results There were no differences in baseline characteristics between the study groups. After 12 months 11 patients died (6 in the group where the ACEI was initiated). At 12 months the group receiving carvedilol as initial therapy achieved a higher tolerable dose of carvedilol (43 ± 17 mg vs. 33 ± 18 mg, p = 0.03); a lower dose of furosemide (p l 0.05); and better improvements in symptoms (NYHA FC, p l 0.002), LV ejection fraction (radionuclide: 15 ± 16% vs. 6 ± 13%, p l 0.05; echocardiographic, p l 0.01), and plasma N-terminal pro-brain natriuretic peptide concentrations (p l 0.02). Conclusions As opposed to the conventional sequence of drug use in the treatment of heart failure, initiation of therapy with carvedilol before an ACEI results in higher tolerable doses of carvedilol and better improvements in FC and LV function.

Objectives. The aim of this study was to determine whether left ventricular dilation and congestive heart failure in patients with acute rheumatic fever with carditis are accompanied by left ventricular contractile dysfunction.Background. Acute rheumatic fever with carditis involves both the myocardium and endocardium, with consequent valvular regurgitation. The relative contribution of volume overload induced by valvular regurgitation and myocardial dysfunction due to rheumatic myocarditis to the overall degree of left ventricular dilation and congestive heart failure in these patients is unknown.Methods. To investigate this, we evaluated 32 patients (15 male, 17 female, mean age 14 ± 3 years) with documented active carditis and congestive heart failure. All 32 patients were found to have significant isolated mitral regurgitation or combined mitral and aortic regurgitation. Echocardiographic analysis of left ventricular dimensions and systolic performance was performed before and after isolated mitral or combined mitral and aortic valve replacement and the results were compared with those in 19 control subjects matched for age, gender and body surface area.Results. Both preoperative left ventricular end-diastolic diameter and percent fractional shortening were significantly increased in patients compared with control subjects (57 ± 7 vs. 43 ± 3 mm, p < 0.001, and 38 ± 6% vs. 33 ± 1%, p < 0.001, respectively). After valve replacement, left ventricular end-diastolic diameter decreased significantly (57 ± 7 to 47 ± 6 mm, p < 0.001). Although percent fractional shortening decreased significantly postoperatively (38 ± 6% to 32 ± 6%, p < 0.001), the postoperative percent fractional shortening did not differ from that in control subjects (32 ± 6% vs. 33 ± 1%, p = NS).Conclusions. The results of this study indicate that left ventricular dilation and heart failure in patients with acute rheumatic carditis rarely occur in the absence of hemodynamically significant regurgitant valve lesions. Furthermore, rapid reduction in left ventricular dimensions and preservation of fractional shortening after isolated mitral or combined mitral and aortic valve replacement suggest that rheumatic carditis is not accompanied by any significant degree of myocardial contractile dysfunction.

From January 1982 to December 1988, 203 consecutive patients were selected for early valve replacement (mean 10 days from time of admission) if they had clinical evidence of native valve endocarditis with 1) vegetations on echocardiography, 2) severe valvular lesions, and 3) heart failure. Surgery was performed within 7 days of admission in 56% of patients and was done urgently because of hemodynamic deterioration in 108 (53%). All vegetations were identified by echocardiography and confirmed macroscopically at surgery.One hundred ten patients had isolated aortic valve infection, 50 had isolated mitral valve infection (p < 0.05 for aortic vs. mitral) and 43 had double-valve infection. Mean aortic cross-clamp time was 57, 38 and 67 min, respectively. Sixty-four patients (32%) had extensive infection involving the anulus or adjacent tissues, or both; such infection more frequently involved the aortic than the mitral valve (p < 0.05). Thirty-eight patients (35%) with aortic valve infection had abscess formation compared with 1 patient (2%) with mitral valve infection (p < 0.05). Only eight patients (4%) died in the hospital. There were seven patients (3%) with a periprosthetic leak and five patients (3%) with early prosthetic valve endocarditis. Long-term follow-up, available in 174 hospital survivors (89%), revealed 10 deaths and two new ring leaks at 38 ± 22 months.In conclusion, among patients with endocarditis who need surgery for heart failure, aortic valve infection is more prevalent than mitral valve infection and is more often associated with extensive infection, including abscess formation. However, even the presence of heart failure and extensive infection is not necessarily associated with high surgical risk when surgery is performed early.

Objectives. The study was designed to critically evaluate the clinical utility of ejection phase and nonejection phase indexes of contractile state in patients with severe left ventricular dysfunction. Background. Ejection phase indexe of left ventricular systolic performance are unable to differentiate contractility changes from alterations in loading conditions. Isevolumetric and end-systolic force-velocity indexes have been proposed as alternative measurements of contractile state that are load independent. Methods. Seventeen patients with nonischemic dilated cardiomyopathy were studied during cardiac catheterization. High fidelity central aortic and left ventricular pressure measurements were made with simultaneous echocardiographic recordings of chamber minor- and long-axis dimensions and wall thickness. Data were acquired under control conditions, during nitropusisside infusion and with dopamine (6μg/kg per min). Results. Patients were classified into those without (group 1, n = 10) and those with (group 2, n = 7) a decrease in end-diastolic circumferential wail stress in response to dopamine. There were no baseline differences between the groups in functional class, left ventricular chamber geometry or cardiovascular hemodynamics. Ejection phase indexes were variably altered by changes in preload, afterload and heart rate, thereby complicating physiologic interpretation of data. Dopamine increased the commonly used isovolumetric index, maximal rate of rise in left ventricular pressure (dP/dtmax, by 64% for group 1 but by only 16% for group 2 (p < 0.001), resulting in an underestimation of contractile state change in 41% of patients. In contrast, the left ventricular end-systoic circumferential wall stress-rate-corrected velocity of fiber shortening relation, which incorporates afterload, ventricular wall mass and heart rate in its analysis, was a sensitive contractility measurement that was preload independent and equally augmented by dopamine for both groups. Conclusions. Of the left ventricular contractility indexes evaluated, the end-systolic circumferential wall stress-rate corrected velocity of fiber shortening relation was the most physiologically appropriate for assessing pharmacologically induced changes in inotropic state that were accompanied by complex alterations in loading conditions in patients with dilated cardiomyopathy.

The acute hemodynamic effects of an i.v. bolus of verapamil, 0.1 mg/kg or 0.06-0.075 mg/kg, were examined by serial radionuclide studies in 46 patients with coronary artery disease. In 20 patients with ejection fractions (EFs) greater than 35% (group 1A), verapamil, 0.1 mg/kg given over 1-11/2 minutes, had a biphasic effect: first, a transient decrease in EF accompanied by increased left ventricular (LV) volumes and cardiac output equivalents; then, an overshoot of EF to values above control, accompanied by a decrease in peripheral vascular resistance and a drastic decrease in LV volumes, while cardiac output equivalent remained slightly elevated. In eight patients with EFs less than 35% (group 1B), only the first effect on EF was noted. In 10 patients with EFs greater than 35% (group 2), verapamil, 0.06-0.075 mg/kg, exerted qualitatively similar but milder effects on hemodynamic function. Finally, verapamil, 0.1 mg/kg given more slowly, over 2-21/2 minutes, produced no significant changes in EF or LV volumes in another eight patients (group 3). The acute effects of verapamil are thus both time-related and dose-dependent. They are also related to the baseline functional reserve of the left ventricle. This study documents that verapamil exerts a depressant effect on LV function. However, the transient nature of this depression and the quick recovery to normal or above-normal values indicate that verapamil, in the doses used in this study, is safe to use intravenously in patients with coronary artery disease.

Doppler echocardiographic indexes of ventricular inflow have been used clinically to characterize left ventricular (LV) diastolic function. The reliability of these indexes as markers for intrinsic myocardial diastolic properties has been questioned. Micromanometer left atrial (LA) and LV pressures as well as transmitral Doppler flow velocity signals and M-mode and 2-dimensional echocardiograms were simultaneously recorded. These unique measurements were acquired in patients with dilated cardiomyopathy under baseline conditions and during infusion of high dose amrinone. The response to amrinone was chosen as a hemodynamic model because this drug has previously been described as having beneficial effects on overall LV systolic and diastolic performance. At peak amrinone effect, LV contractility increased (as assessed using load independent end-systolic indexes) and early diastolic relaxation improved whereas passive chamber stiffness, heart rate and stroke volume were unchanged. There was a significant decrease in LV end-diastolic pressure as well as a parallel downward shift of the entire LV diastolic pressure-dimension relation. These findings, which indicated an improvement in overall LV diastolic properties, probably represent the combination of more rapid early diastolic relaxation in conjunction with a reduction in venous return, the relief of pericardial restraint or the reduction in right ventricular-LV interaction. In contrast, the ratios of Doppler-determined peak transmitral early-to-late flow velocities and early-to-late diastolic flow velocity integrals decreased with amrinone infusion, thereby suggesting a drug-induced decrease in LV diastolic compliance. Thus, in patients with idiopathic dilated cardiomyopathy, administration of amrinone has a complex effect on LV diastolic properties. In these patients the most commonly used Doppler criteria for LV filing properties have to be used cautiously because the derived conclusions may be diametrically opposed to the actual hemodynamic changes.

Previous reports indicate an increased risk of thrombotic and embolic events in patients with mechanical heart valve prostheses during pregnancy. We prospectively followed 50 pregnancies in 49 patients with 62 cardiac prostheses from presentation at the antenatal clinic through the remainder of the pregnancy. Of the 60 mechanical prostheses, 39 were Medtronic-Hall, 7 St. Jude Medical, 7 Starr-Edwards and 7 Bjork-Shiley. Forty-three patients were in New York Heart Association functional class I or II and 6 were in functional class III or IV. Forty-five patients were in sinus rhythm and 4 had chronic atrial fibrillation. All patients received warfarin during the first and second trimesters. Forty-one pregnancies proceeded beyond 28 weeks. In 23 of these (group I) warfarin was replaced with heparin at 36 weeks gestation. In the remaining 18 (group II) warfarin was not substituted owing to premature onset of labor. The target prothrombin ratio (international normalized ratio) in patients receiving warfarin was 2.0 to 2.5. The partial thromboplastin time was maintained at 1.5 to 2.5 times the control value in patients receiving heparin. Eleven patients received dipyridamole plus warfarin for the duration of pregnancy. There were no maternal thromboembolic complications or deaths associated with pregnancy. Antepartum hemorrhage occurred in 1 patient at 35 weeks gestation. One patient (group I) experienced peripartum hemorrhage. All patients were hemodynamically stable before delivery, but 2 developed pulmonary edema during labor. The mean fetal birth weight was low (2.54 ± 0.98 kg). There were 9 abortions (18%), 7 stillbirths (14%), 2 neonatal deaths (4%) and 2 instances of warfarin embryopathy (4%). Fetal outcome was not affected by New York Heart Association functional class. Only 39% of prothrombin ratios were within or greater than the target range. The incidence of thromboembolism is low in pregnant patients with newer generation mechanical heart valves even in the presence of low levels of anticoagulation. Although a high rate of fetal wastage and neonatal mortality associated with warfarin anticoagulation is confirmed, neonatal morbidity and maternal risk are low. It is concluded that pregnancy is not contraindicated in patients with newer generation mechanical heart valves.

Viral myocarditis may present with a variety of electrocardiologic aberrations. Torsade de pointes, a potentially malignant ventricular arrhythmia associated with prolongation of the QT interval has not been described in patients with acute viral myocarditis. This report details this finding in a patient with coxsackie B3 myocarditis in whom symptomatic torsade de pointes was documented.