Nifedipine blockade of ergonovine-induced coronary arterial spasm: angiographic documentation.

To determine whether calcium-flux blockade with nifedipine blunts coronary vasospasm, four patients with angiographically demonstrable coronary arterial spasm in the absence of significant fixed coronary arterial stenosis were evaluated with coronary arteriography before and after treatment with nifedipine. After initial coronary arteriography, ergonovine was administered in successive doses of 0.05, 0.1 and (when necessary) 0.2 mg intravenously at 3 minute intervals. Three patients had symptomatic high grade focal coronary arterial spasm with electrocardiographic changes, and the fourth exhibited asymptomatic 60 percent constriction of the left anterior descending coronary artery. A maximal ergonovine challenge was repeated 30 minutes later after each patient had been pretreated with a 20 mg sublingual dose of nifedipine. Under these conditions, no patient had chest pain or electrocardiographic changes. Furthermore, neither focal nor diffuse coronary arterial spasm was demonstrable angiographically after the second challenge. Thus, in each case, a single dose of nifedipine precluded the angiographic expression of ergonovine-provoked coronary arterial spasm.

Failure of Beal mitral valve prosthesis. Clinical and radiographic features.

This report presents a case of severe dysfunction of an improved Model 104 Beall valve secondary to disc wear. This type of valve failure may be extremely difficult to detect by auscultation, echocardiography, or fluoroscopic examination. Prosthesis failure with resulting mitral insufficiency should be considered in any patient with a Teflon disc Beall mitral valve in whom there is unexplained clinical deterioration.

Congenital arteriovenous malformations between brachiocephalic arteries and systemic veins.

Three patients under two years of age are described with unusual fistulas involving the brachiocephalic arteries and the innominate vein or the superior vena cava. Two patients were asymptomatic, and one newborn was cyanotic and in congestive failure. This unusual presentation has only rarely been reported in thoracic arteriovenous malformations. Two of the three patients underwent successful surgical repair. Two-dimensional echocardiography aids in the evaluation of these patients, but cardiac catheterization and angiography are indispensable diagnostic techniques for documenting the extent and location of these lesions and thus guiding proper therapy.

Chest film diagnosis of disc embolization in patients with Beall mitral valve prostheses.

This report presents the chest film findings in three patients with Beall mitral valve prostheses in whom severe disc wear resulted in disc embolization. In all three cases the worn disc embolized to the thoracic aorta with catastrophic decompensation, and all three patients were salvaged with emergency operation. Detection of the embolized disc was possible with plain chest radiography in each case and may permit removal of the embolized disc at the time of valve replacement. Early detection of disc wear and replacement of worn Beall mitral valve prostheses are advocated to avoid this left-threatening complication.

Surgical management of hypoplastic right ventricle with pulmonary atresia or critical pulmonary stenosis and intact ventricular septum.

Our experience with the surgical management of hypoplastic right ventricle with intact ventricular septum includes 26 patients with pulmonary atresia and 4 with critical pulmonary stenosis. Group 1 consisted of 8 neonates managed initially by transventricular valvotomy; 6 later required a secondary procedure, with 100% survival. Group 2 had 11 neonates managed by aorta-pulmonary artery shunting without operative death. However, only 3 have survived over the long term and 1 has required an additional shunt procedure. Group 3 had 9 infants who underwent concomitant valvotomy and shunting. There were 4 operative deaths and 1 late death. Finally, Group 4 included 2 infants managed by primary repair at 3 days and 6 days old with prosthetic enlargement of the right ventricle; 1 required the addition of a shunt. Both are alive. Seven of the 15 patients in Groups 1, 2, and 3 who survived neonatal palliative procedures have undergone reparative operations. Two had no growth of the right ventricle and underwent repair after conversion to tricuspid atresia, by a Fontan procedure. Five had prosthetic enlargement of the right ventricle in childhood with 1 late death. Findings of this review were as follows: (1) effective palliation of pulmonary atresia and intact ventricular septum or critical pulmonary stenosis with cavitary hypoplasia of the right ventricle is rare unless transventricular flow can be established; (2) establishment of transventricular flow produces a high incidence of cavitary "growth," which permits later repair; (3) the Fontan operation is available for repair in patients who have no cavitary growth; and (4) when all three portions of the right ventricular cavity can be identified by angiography, a primary repair can be performed in the neonatal period with a good long-term prognosis.

A new operation for far-advanced cystic medial necrosis of the aortic root.

Three patients with far-advanced cystic medial necrosis of the aorta, which had produced giant bulbous enlargement of the aortic root and severe aortic regurgitation, were operated on using a procedure not previously described. Measurements of the aortic valve annulus and ascending aorta were made from aortograms. A knitted polyester arterial prosthesis was sewn together to form a circle. This circular prosthesis was sewn to a 31 mm Björk-Shiley aortic valve prosthesis in the way that a tire is fitted onto a wheel. The resulting composite prosthesis, which had the same diameter as the aortic root, was used to replace the excised valve. In all cases a composite prosthesis measuring greater than 50 mm in diameter was used. In 2 of the 3 patients the ascending aorta was replaced with a tubular graft reshaped as a truncated cone. This reshaping was done by inserting multiple gussets into one end of the aortic prosthesis so that the flanged end fit precisely to the transverse aortic arch. Two patients are asymptomatic more than two years following operation. The third patient died suddenly of a ventricular arrhythmia on the twenty-third postoperative day.

Experimentally reversed pulmonary blood flow. Implications for the surgical management of complex forms of congenital heart disease.

Blood flow to the right lung was reversed in 28 dogs, 14 of which survived more than 1 month. Four successful long-term survivors (1 years to 4 years 7 months) were repeatedly studied by cardiac catheterization, angiography, and ventilation/perfusion scans as well as hemodynamically when they were killed. Hemodynamics and gas transfer were normal up to 4 1/2 years after the procedure, and the histology of the right lung was essentially normal. The application of reversed pulmonary blood flow is proposed in the surgical management of forms of congenital heart disease in which the right ventricle is diminutive. The procedure consists of repartitioning of the atria to allow venous blood to flow into the lung through the pulmonary veins and exit to the left atrium through the pulmonary artery.

Late clinical problems with Beall model 103 and 104 mitral valve prostheses: hemolysis and valve wear.

The purpose of this study was to determine the influence on hemolysis of the spatial orientation of the struts in the Beall mitral valve prosthesis, Models 103 and 104. Thirteen pairs of patients were selected to match struts oriented parallel and perpendicular to the left ventricular outflow tract axis. The average time after operation was 3.73 years. Complete blood counts and relative serum chemistry values were determined.

Digital venous angiography in the diagnosis of pulmonary thromboembolism.

Twenty-five patients with the clinical suspicion of pulmonary thromboembolism underwent venous digital subtraction angiography (DSA) concurrently with selective conventional pulmonary angiography and the results were compared by two independent observers. Our conclusion is that venous DSA lacks adequate specificity and sensitivity for the diagnosis of pulmonary thromboembolism in subsegmental pulmonary arteries. Any benefit derived from this slightly less invasive technique is far outweighed by the decrease in technical detail when compared to the selective film screen method.

Influence of right ventricular hemodynamics on left ventricular diastolic pressure-volume relations in man.

To clarify the mechanism of displacement of the left ventricular diastolic pressure-volume function with alteration of loading conditions, the effects of nitroglycerin on pressure-volume relations in 13 patients were compared with those of amyl nitrite in 13 other patients during cardiac catheterization. After nitroglycerin, average systemic mean arterial pressure declined by 15.1 mm Hg (17%) and left ventricular end-diastolic pressure by 9.4 mm Hg (49%); right ventricular systolic and end-diastolic pressures fell 11.6 mm Hg (36%) and 5 mm Hg (41%), respectively. In all patients diastolic pressure-volume curves were significantly displaced downward and leftward. After amyl nitrite, average systemic mean arterial pressure fell 20.1 mm Hg (22%), but left ventricular end-diastolic pressure and right ventricular systolic and end-diastolic pressures were not significantly reduced. No significant displacement of diastolic pressure-volume curves occurred. Both the rate constant of the exponentially fit diastolic pressure-volume curve, and the rate of diastolic isovolumic relaxation (T) were unchanged after each drug. Thus downward displacement of diastolic pressure-volume functions after nitroglycerin appears to be dependent more upon reduction of right ventricular filling dynamics than coronary perfusion pressures. More favorable effects upon left ventricular function may be associated with reduction of both left ventricular filling pressures and systemic impedance (reflecting both "preload" and "afterload") than of systemic arterial pressures ("afterload") alone.

The radiographic appearance of coronary artery dissection: a decision-making dilemma.

The appearance of acute iatrogenic dissection of the coronary arteries during coronary angiography is described in five patients. Specific signs of dissection include: 1) initimal flap, 2) delayed flow, 3) loss of side branches, 4) periostial contrast "puddling," and 5) unusually small size coronary artery with atypical smooth walls. Recognition of the radiographic patterns of this complication should permit distinction from coronary spasm, thrombosis, and embolization. Recent advent of alternate forms of therapy (streptokinase infusion, angioplasty) makes it imperative to precisely diagnose the dissection to avoid possible catastrophic results.

Diagnosis of congenital absence of left pericardium by MR imaging.

Congenital absence of the pericardium, whether partial or total, is a rare abnormality. It can be very difficult to diagnose clinically as well as to confirm radiographically. Plain film fluoroscopy and CT have been shown to be of value in differentiating this entity from others with similar findings. We report a case in which magnetic resonance was utilized to confirm the diagnosis and the findings of this new technique are described.

CT diagnosis of type A aortic dissections not demonstrated by aortography.

False-negative aortography in a patient with a type A dissection is an unusual and serious diagnostic error. We report three cases of type A thoracic dissections with negative aortography but positive CT or magnetic resonance. The factors that might account for this discrepancy and the implications in the evaluation of these patients are discussed.

Cineangiography in the diagnosis and evaluation of aortic dissection.

Fourteen patients with suspected aortic dissection were studied with 35-mm biplane cineangiography, and the results were compared with those of previously obtained conventional large-film studies. There was no loss of radiographic information due to the decreased resolution of the cine technique. The detection of initial dissection sites, reentry points, and intimal flaps, and the evaluation of aortic regurgitation and the coronary ostia may be improved with cineangiography. The procedure time was shortened and repeat examinations were eliminated with the cine method. Consideration of this technique in evaluating aortic dissection is recommended.

Pulmonary perfusion abnormalities and ventilation-perfusion imbalance in children after total repair of tetralogy of Fallot.

The pulmonary perfusion of 25 children who had total surgical correction of tetralogy of Fallot was evaluated by radionuclide perfusion scans. In addition, 18 had 133Xe ventilation studies. Eighteen of the children previously had palliative systemic-pulmonary shunts; 14 had aortic-pulmonary shunts (Waterston or Potts-Smith) and four had Blalock-Taussig shunts. Seven children had single stage total corrections. An asymmetric perfusion pattern was found in 13 of 18 children who previously had systemic-pulmonary shunts, including 12 of 14 with previous aortic-pulmonary shunts (P less than 0.05). The most common finding was relative hypoperfusion of the lung which had received the palliative shunt (P less than 0.001). The distribution of ventilation remained relatively symmetric, even when perfusion was markedly abnormal, and this resulted in ventilation-perfusion imbalance in several patients. Asymmetric perfusion was significantly less common in patients who had undergone single stage corrections (P less than 0.05). The findings document the frequent occurrence of residual abnormalities of pulmonary perfusion and ventilation-perfusion imbalance in patients who have palliative aortic-pulmonary shunts prior to total repair, and support the position that single stage correction is preferable to aortic-pulmonary shunting in the surgical management of tetralogy of Fallot.

Ventilation-perfusion studies in suspected pulmonary embolism.

The results of ventilation-perfusion (V-Q) imaging and pulmonary angiography were retrospectively analyzed in 146 patients with suspected pulmonary embolism (PE) to define the frequency of PE associated with various scintigraphic patterns. When the radionuclide images demonstrated at least two moderate-sized or one large area of V-Q mismatch, the probability of PE was 92%. However, only one of three patients with a single moderate-sized V-Q mismatch had PE, while small V-Q mismatches were not associated with PE in any of 19 patients. Matched V-Q abnormalities in lung regions that were radiographically normal were infrequently due to PE (4.8%). When a perfusion defect was substantially smaller than a corresponding radiographic abnormality, the frequency of PE was low (7.7%). Conversely, when a perfusion defect was substantially larger than the corresponding radiographic abnormality, there was a high probability of PE (87%). Matched perfusion and radiographic abnormalities indicated an intermediate probability of PE (27%). Patients with suspected pulmonary embolism may be classified into groups with low, intermediate, or high probability of pulmonary embolism on the basis of size and number of perfusion defects and a careful comparison of perfusion defects with ventilatory and radiographic findings.

The role of 133Xe ventilation studies in the scintigraphic detection of pulmonary embolism.

The angiographic, scintigraphic, and clinical data of 40 patients were reviewed in order to define the role of 133Xe ventilation studies in the radionuclide detection of pulmonary embolism. Two independent observers interpreted the perfusion images, and several weeks later reinterpreted them in conjunction with 133Xe ventilation studies. Overall diagnostic accuracy was significantly improved (p less than 0.05) when the xenon studies were included. The combined studies were slightly more sensitive and significantly more specific (p less than 0.05) for pulmonary embolism than the perfusion images alone.