Biomedical subjects

J E Morch

Publications and source records attributed to J E Morch.

35 records · Page 2Linked to original sources

PubMed1976

Prinzmetal's angina with coronary artery spasm. Angiographic, pharmacologic, metabolic and radionuclide perfusion studies.

We studied the effects of coronary artery spasm on perfusion of the microvasculature in a patient with Prinzmetal's angina. Intracoronary injections of 99mTc and 131I-labelled macroaggregated human serum albumin were performed (1) at rest, (2) during spontaneous angina, (3) after the administration of nitroglycerin and (4) during pacing-induced spasm and the resultant scans compared. The resting scan was normal. Pain and spasm were associated with a perfusion defect that was localized to the anterior and inferior walls of the left ventricle. The localization of the perfusion defect corresponded with angiographically demonstrated spasm involving left anterior descending and distal circumflex coronary arteries. A subsequent myocardial infarction was localized by 43K scanning to the same perfusion area. Metabolic and parasympathetic stimulation studies were performed but were inconclusive. The patient's recurrent pains were ultimately controlled with large oral doses of isosorbide dinitrate.

Angina Pectoris↗

PubMed1976

Angiographic demonstration of blood supply of right atrial myxoma.

A 53-year-old woman underwent cardiac catheterization for assessment of coronary arterial disease. An unexpected finding of a gradient between right atrium and right ventricle led to the discovery of an unsuspected right atrial myxoma. The diagnosis was established by the presence of a filling defect in the right atrial angiocardiogram and by the demonstration of "tumour vessels" by selective right coronary angiography. Selective coronary angiography can visualize the blood supply to an intracardiac tumour and thus confirm the diagnosis preoperatively.

Coronary Angiography↗

PubMed1975

Mitral stenosis with posterior diastolic movement of posterior leaflet.

The echocardiographic diagnosis of mitral stenosis depends in part on the demonstration of abnormal posterior leaflet movement to distinguish it from other conditions that similarly affect anterior leaflet motion. In mitral stenosis the posterior leaflet has been shown to move anteriorly in diastole rather than in the normal posterior direction. A patient presented with clinical evidence of moderate mitral stenosis. The anterior leaflet echo was typical but the posterior leaflet showed posterior diastolic movement. At catheterization moderate mitral stenosis was confirmed. To our knowledge this is the first report of the echocardiographic demonstration of posterior diastolic movement of the posterior mitral leaflet in documented mitral stenosis.

Angiocardiography↗

PubMed1975

Self-conversion of drug-resistant paroxysmal atrial tachycardia.

A 56-year-old woman had paroxysmal atrial tachycardia (PAT) that was recurrent, drug-resistant and required frequent electroversion. The mode of onset and termination of initiated episodes of PAT suggested an AV junctional reentrant mechanism. The problem was successfully managed by a permanent electrode implanted transvenously in the coronary sinus and connected to a subcutaneous radio frequency receiver. For the past 24 months the patient has successfully terminated all episodes of PAT (at least 60) by activating an external radio frequency transmitter that transmits impulses to the implanted receiver and electrode catheter. Conversion to sinus rhythm requires 5 seconds or less of pacing.

Bundle of His↗

PubMed1975

Myocardial infarction in coronary artery surgery.

Myocardial infarction has been noted as a frequent complication of coronary artery surgery in many review series, although its causes are uncertain. Follow-up of 100 patients at 19.7 months (mean) after coronary bypass surgery identified 15 patients with perioperative myocardial infarction as judged by new, significant Q waves after surgery. There were no significnat differences in age, preoperative anginal class, previous infarction, presence of hypertension, hyperlipidemia, or frank glucose intolerance compared with the 85 patients without infarction. Nor was there a significnat difference in coronary artery score, left ventricular end-diastolic pressure, cardiac index, or presence of collaterals. Cardiopulmonary bypass time, duration of anoxic arrest, and number of vessels grafted did not differ. Perioperative infarction always occurred in the territory of a grafted vessel and not in comparably compromised, nongrafted areas. In 13 cases new Q waves appeared in the first 24 hours, and myocardial infarction was not clinically suspected. Eight of the 15 grafts at risk were patent at late follow-up. Mean ejection fraction was not significantly changed postoperatively, but affected segmental wall motion declined in most cases. Five patients with perioperative infarction but no patent grafts improved by only 1 NYHA class (mean), but ten patients with infarction and one or more grafts patent improved by 2.9 NYHA classes (mean). Perioperative infarction could not be correlated with currently recognized patient and operative risk factors. The consistent anatomical relationship suggested that the grafting procedure itself was critical to the occurrence of distal segmental infarction.

Adult↗

PubMed1975

Saphenous vein bypass grafting. Changes in native circulation and collaterals.

One hundred patients were evaluated 12 to 43 months after saphenous vein bypass surgery. The rate of progression of obstructive disease in the native vessels and changes in collateral circulation were analyzed in detail. Fifty-five per cent of preoperatively patent vessels showed progression proximal to the site of graft insertion, 40% proximal to patent grafts; there was distal progression in only 7% of grafted vessels. The progression rate for nongrafted vessels was 14%. Patent grafts were associated with a high rate of disappearance of collaterals to the grafted vessels, while occluded grafts were associated with preservation of collaterals or appearance of new collaterals. Progression of obstructive disease in the native circulation and changes in collaterals did not prevent symptomatic improvement (93% of patients were symptomatically improved).

Adult↗

PubMed1974