Biomedical subjects

J Wisneski

Publications and source records attributed to J Wisneski.

4 recordsLinked to original sources

PubMed1982

Comparison of myocardial thallium-201 clearance after maximal and submaximal exercise: implications for diagnosis of coronary disease: concise communication.

Recently the quantitation of regional thallium-201 clearance has been shown to increase the sensitivity of the scintigraphic detection of coronary disease. Although TI-201 clearance rates might be expected to vary with the degree of exercise, this relationship has not been explored. We therefore evaluated the rate of decrease in myocardial TI-201 activity following maximal and submaximal stress in seven normal subjects and 21 patients with chest pain, using the seven-pinhole tomographic reconstruction technique. In normals, the mean TI-201 clearance rate declined from 41% +/- 7 over a 3-hr period with maximal exercise to 25% +/- 5 after 3 hr at a submaximal level (p less than 0.001). Similar differences in clearance rates were found in the normally perfused regions of the left ventricle in patients with chest pain, depending on whether or not a maximal end point (defined as either the appearance of ischemia or reaching 85% of age-predicted heart rate) was achieved. In five patients who did not reach these end points, 3-hr clearance rates in uninvolved regions averaged 25% +/- 2, in contrast to a mean of 38% +/- 5 for such regions in 15 patients who exercised to ischemia or an adequate heart rate. These findings indicate that clearance criteria derived from normals can be applied to patients who are stressed maximally, even if the duration of exercise is limited, but that caution must be used in interpreting clearance rates in those who do not exercise to an accepted end point.

Adult↗

PubMed1979

Mild ventricular dysfunction following cold potassium cardioplegia.

The long-term effects of cold potassium cardioplegic arrest was examined in 40 patients who underwent myocardial revascularization. Comparisons between resting ejection fraction (EF), end diastolic volume (EDV), and segmental wall motion were made between the preoperative and postoperative catheterization (mean postoperative recatheterization, 6 months). A 2.93 graft per patient ratio was found in this group of patients, with 108/117 grafts visualized at the time of recatheterization. The EF was 60% +/- 3% before surgery and 62% +/- 3% after surgery. A correlation coefficient of 0.91 was determined for the entire series. The EDV was 151 +/- 16 cc before coronary artery bypass graft (CABG) and was unchanged post CABG at an end diastolic volume of 137 +/- 15 cc. Analysis of preoperative wall motion of 33 patients demonstrated 111 depressed segments, 68 normal, and 52 hypercontractile; at recathetrization, there were 100 depressed, 66 normal, and 65 hypercontractile segments. Although there was essentially no deterioration of myocardial function for 37 out of 40 patients, three demonstrated a reduction in EF, the largest reduction being 15%. These three patients had a cardioplegic arrest time greater than 70 minutes. An inverse relationship between percent change in EF and the length of cardioplegic arrest was observed, with an r value o - 0.57 (p less than 0.01). These data suggest that prolonged cardioplegic arrest times may be associated with mild dysfunction. Cold potassium cardioplegic arrest up to 70 minutes was associated with no change in EF, EDV, or wall motion in this series of patients.

Cardiac Catheterization↗

PubMed1977

The impact of coronary artery bypass on late myocardial infarction.

Two hundred consecutive patients undergoing coronary artery bypass for stable and unstable angina pectoris were followed clinically 3 to 53 months (mean 27) and with serial electrocardiograms (ECG's) 3 to 43 months (mean 18.5) postoperatively. Complete (twelve lead) resting ECG data including preoperative, early postoperative (in hospital), and late (post hospital) studies were available in 98 per cent (196/199) of hospital survivors. A total of 2,304 ECG's were examined by two cardiologists for a total follow-up of 3,629 patient months. Myocardial infarction was defined as the appearance of a new, significant (Minnesota Code) Q wave. Fifty-four per cent (108/200) had triple vessel disease and 24 per cent (47/200) preinfarction angina pectoris by strict criteria. There was one hospital death for an operative mortality of 0.5 per cent (1/200). There was one late fatal and three late nonfatal myocardial infarctions. Seventeen patients developed new Q waves in the early postoperative period, a perioperative infarction rate of 8.5 per cent (17/200). The 43 month cumulative myocardial infarction rate, including all early and late postoperative new Q waves and three late deaths from cardiac disease, was 14 per cent. Twenty-two per cent (20/91) showed disappearance of Q waves present at the time of hospital discharge. These data suggest that the late myocardial infarction rate is low in surgically managed patients.

Adult↗

PubMed1975

Improved survival after coronary artery surgery in patients with extensive coronary artery disease.

Survival in patients with ischemic heart disease is closely related to the extent of coronary artery obstruction as determined angiographically. One hundred forty-nine consecutive patients underwent coronary artery bypass surgery from November, 1971, to October, 1974. There were 2 late cardiac deaths, 1 late noncardiac death, and 1 hospital death, an operative mortality rate of 0.7 per cent and a total mortality rate of 2.7 per cent. Coronary angiograms were scored according to the method of Friesinger, Page, and Ross. Fifty-four per cent (80/149) had scores of 10 or greater. Cumulative survival was analyzed according to life-table techniques; in the 80 surgically managed patients with scores of 10 or greater, survival at 3 years was 98 per cent. Friesinger's 47 nonoperated patients with similar angiographic scores had a 3 year cumulative survival of 68 per cent. Although this study compares different groups, the surgical series was composed of older patients (mean age 52 as compared to 44 years), includes 22 patients operated on urgently for preinfarction angina pectoris, and includes 18 patients with abnormal ventricular function. These data suggest that coronary artery bypass surgery can favorably influence prognosis in patients with severe coronary artery disease.

Adult↗