Aubrey Pitt

Myxoma of the Left Atrium Hemodynamic and Phonocardiographic Consequences of Sudden Tumor Movement

Two patients with myxoma of the left atrium were studied by left heart catheterization and cineangiography, and the diagnosis was confirmed at operation in both cases. An electrocardiographic timing signal on the cineradiographs permitted correlation of heart sounds and pressure waves with movement of the tumor between the left atrium and the left ventricle. In early systole, the tumor suddenly moved from the left ventricle to the left atrium, and a notch in the rising left ventricular pressure, a prominent c wave, and loud, late elements of the first sound were noted. In early diastole, the tumor moved rapidly through the mitral valve, causing an abrupt diminution in the left atrial volume, thus causing a rapid y descent despite severe obstruction of the mitral valve. An early diastolic sound, thought to be an opening snap, appeared to be related to the checking of the tumor in the left ventricle (“tumor plop”).The unusual left atrial pressure pulse seen in these two cases resembles data from other cases of myxoma reported in the literature, and recognition of these unusual pressures may permit accurate preoperative diagnosis in other patients. Diagnostic changes may be present on apexcardiograms.

Radionuclide angiographic assessment of global and segmental left ventricular function at rest and during exercise after coronary artery bypass graft surgery.

Left ventricular ejection fraction (LVEF) was measured by radionuclide angiography at rest and during supine bicycle exercise before and 3 months after coronary artery bypass graft surgery (CABG) in 20 patients with chronic stable angina. The right anterior oblique gated first-pass technique was used to assess LVEF response to maximal exercise (Wmax), while the left anterior oblique equilibrium-gated technique was used to assess LVEF and relative LV volume changes during graded submaximal exercise. Mean LVEF was unchanged at rest after CABG by both the first-pass (60 12% vs 60 ± 12%) and equilibrium-gated (61 ± 13% vs 62 ± 13%) measurements. At Wmax, mean first-pass LVEF was significantly higher postoperatively than preoperatively (63 ± 17% vs 53 ± 17%; p < 0.01), with a higher Wmax (750 ± 182 vs 590 ± 202 kpm/min; p < 0.001) and higher rate-pressure product (302 ± 59 vs 222 ± 57 units; p < 0.001). Similarly, equilibrium-gated LVEF levels during graded exercise, using stepwise regression analysis, were significantly higher postoperatively than preoperatively (p< 0.001); at the highest graded work load, they averaged 63 ± 19% postoperatively and 53 ± 17% preoperatively, with higher work loads (500 ± 190 vs 417 ± 155; p< 0.05) and higher rate-pressure products (271 ± 55 vs 207 53; p< 0.001). The increase in exercise LVEF after surgery was due to a marked decrease in the ratio, relative to resting values, of counts-based end-systolic volumes during submaximal exercise (preoperative 1.91 ± 1.04; postoperative 1.14 ± 0.46; p< 0.01). The five subjects in whom LVEF decreased significantly during exercise postoperatively all had one or more blocked or stenosed grafts. This study documents, by two independent radionuclide techniques, an improved LVEF during exercise at an increased maximal work capacity and rate-pressure product 3 months after successful CABG.

Pulmonary embolism secondary to anomalies of deep venous system of the leg.

Two cases of recurrent pulmonary emboli secondary to thrombosis in anomalies of the deep veins of the lower limb are presented. In both cases the source of emboli was not evident clinically, and it was only after venography that the venous anomalies were discovered, both being confined to one limb and amenable to surgical intervention. Such anomalies have not previously been reported as sources of venous thromboembolism in adults. The importance of venography in establishing the source of pulmonary emboli, especially when recurrent, is stressed.

Induction of ventricular arrhythmias by programmed ventricular stimulation: a prospective study on the effects of stimulation current on arrhythmia induction.

A protocol for programmed ventricular stimulation is described in which the effect of increasing stimulation current on ventricular refractoriness and arrhythmia induction was specifically examined. The protocol was evaluated prospectively in 70 patients undergoing electrophysiological study for documented or suspected ventricular arrhythmias. Programmed electrical stimulation was performed at the right ventricular apex and outflow tract using single and double extrastimuli and burst pacing. Stimulation currents of 2, 5, 10, and 20 mA were used in ascending order. The initial (lowest) current was never less than twice diastolic threshold and was maintained during each stimulation run until refractoriness was reached. The current was then increased to the next level to facilitate premature capture until refractoriness was encountered at 20 mA or a sustained arrhythmia occurred. Ventricular arrhythmias were induced in 34 patients, 31 of whom had presented with a sustained ventricular arrhythmia. The incidence of induced arrhythmias was low in those patients who had presented with symptoms alone, a non-sustained arrhythmia, or a sustained arrhythmia in association with a predisposing clinical event. Only one patient with a negative result had further ventricular arrhythmias during the mean follow up period of 15 months. Although each increase in stimulation current caused a decrease in measured ventricular refractoriness, this resulted in only four arrhythmias. Only one arrhythmia was induced above 5 mA. These results suggest that this simple protocol using two extrastimuli and a single stimulation current of 5 mA will reliably identify most patients who have symptomatic ventricular arrhythmias.

Intrapericardial Cyst Formation in Constrictive Pericarditis Simulating Tricuspid Stenosis

Two cases of constrictive pericarditis with intrapericardial cyst formation are presented. In each, a tricuspid diastolic murmur was present, and confirmation of a tricuspid valve gradient was obtained at cardiac catheterization. Angiographic studies revealed that the tricuspid valves were distorted by the cysts. In both patients, surgical excision was successfully achieved.In case 1 a blood-containing cyst was found, the etiology of which is obscure. Case 2 was associated with rheumatoid arthritis, and the compression resulted from a chronic abscess that probably arose at a previous pericardiectomy.

An unusual tumour involving heart and liver

Abstract We report the successful removal of a large right atrial haemangioma associated with multiple liver haemangiomas. Preoperative echocardiography showed a large right atrial mass, and computerised tomography revealed lesions in the liver. A preoperative diagnosis of malignant cardiac tumour and liver secondaries was made. However, the tumour was benign. This case emphasises the need to obtain a definitive histologic diagnosis preoperatively, if possible, before rejecting a patient for surgery, and to be aware that benign lesions can be multifocal.