Biomedical subjects

G A Slavich

Publications and source records attributed to G A Slavich.

6 recordsLinked to original sources

PubMed1999

Gated Tc-99m sestamibi SPECT versus stress-rest SPECT in detecting coronary artery disease: correlation with coronary angiography in patients without myocardial infarction.

PURPOSE: It is possible to simultaneously evaluate wall thickening and perfusion abnormalities with radionuclide techniques that use tracers such as Tc-99m MIBI. We presumed that detection of wall thickening by gated MIBI SPECT imaging in the presence of a stress-induced perfusion defect correlates with reversibility of that defect on resting images. Therefore, the aim of our study was to analyze, in patients without myocardial infarction, resting wall thickening and stress perfusion imaging as an alternative to conventional stress-rest imaging. METHODS AND RESULTS: The patients (n = 44) underwent an exercise (n = 37) or pharmacologic (n = 7) stress protocol. All patients had previous coronary angiography within 3 months. Stress-rest MIBI SPECT and gated MIBI SPECT studies were analyzed by visual scoring. The sensitivity and specificity of segmental analysis of both stress-rest MIBI SPECT perfusion and gated MIBI SPECT studies for the overall detection of coronary artery disease were, respectively, 71% and 96%. For patient evaluation for detection of coronary artery disease, stress-rest MIBI SPECT perfusion and gated MIBI SPECT studies showed a sensitivity rate of 96% for both and specificity rates of 84% and 79%, respectively. CONCLUSIONS: Our data revealed close agreement between reversible perfusion defects on stress-rest MIBI SPECT scans and significant wall thickening on gated MIBI SPECT stress images in patients without previous myocardial infarction (95%). Gated MIBI SPECT stress, without resting studies, which provide an assessment of wall motion and wall thickening, potentially allows stress defect reversibility to be evaluated in patients without previous myocardial infarction.

Adult↗

PubMed1998

Myocardial viability: known and unknown.

The assessment of myocardial viability has gained a lot of attention over the past few years. Various imaging techniques, mainly nuclear and echocardiographic approaches, have been developed for this purpose. From the existing data, it has become clear that the presence of dysfunctional yet viable myocardium can predict improvement of regional and global left ventricular (LV) function after revascularization. This issue is most relevant in patients with severely depressed LV function, since in these patients revascularization carries a high (peri-)procedural risk on the one hand, but may substantially improve LV function in some patients. Besides the improvement of resting LV function after revascularization, other end-points may also be clinically relevant, including the response during stress, improvement of exercise capacity, the quality of life and the prevention of LV remodeling. These issues have not been studied extensively thusfar. Finally, several retrospective studies have shown the prognostic value of viability assessment; patients with viable but jeopardized myocardium were significantly more prone to experience cardiac events than patients with viability who underwent revascularization. The different aspects of viability assessment (including pathophysiology, available techniques, current implications and unresolved issues) will be addressed in this manuscript.

Cardiomyopathies↗

PubMed1997

Cardiac magnetic resonance imaging findings in patients with right ventricular outflow tract premature contractions.

AIMS: To assess prospectively the value of cardiac magnetic resonance imaging in patients with apparently idiopathic premature contractions arising from the right ventricular outflow tract. METHODS: We compared magnetic resonance imaging scans in 19 patients (13 males and six females, mean age 44 years) with frequent (> 100 per hour), monomorphic (left bundle branch block and inferior axis morphology) extrasystoles, and in 10 volunteers (four males and six females, mean age 36.7 years) without structural heart disease. Magnetic resonance imaging studies (1 or 1.5 Tesla) included spin-echo and gradient-echo sequences in the standard planes. The presence of structural and dynamic abnormalities of the right and left ventricles, such as reduced wall thickness, systolic bulging, and decreased systolic thickening, were evaluated. In addition, end-diastolic diameters of the right ventricular outflow tract were measured in the transverse plane. RESULTS: The dimensions of the right ventricular outflow tract were wider in patients with extrasystoles compared to the control group. Mean anteroposterior and transverse diameters were 39.6 +/- 4.6 mm vs 29.9 +/- 4.8 mm (P < 0.01) and 27.5 +/- 3.8 mm vs 20.5 +/- 2.5 mm (P < 0.01), respectively. Wall motion and morphological abnormalities were present in 16/19 (84%) patients, and were confined to the anterolateral wall in 15/16 cases. All normal subjects had normal magnetic resonance imaging findings (P = 0.008). CONCLUSIONS: Cardiac magnetic resonance imaging revealed that in patients with idiopathic right ventricular outflow tract premature contractions there was a higher rate of morphological and functional abnormalities of the right ventricular outflow tract than in the normal subjects. Large studies and long follow-up are needed to confirm whether these findings could help identify a localized form of arrhythmogenic cardiomyopathy, and its clinical significance.

Adolescent↗

PubMed1996

Feasibility of simultaneous Tc99m sestamibi and 2D-echo cardiac imaging during dobutamine pharmacologic stress. Preliminary results in a female population.

Feasibility of simultaneous 2D-Echo and SPECT Tc99m Sestamibi imaging during dobutamine infusion was evaluated in a female population with suspected coronary artery disease and scheduled for diagnostic coronary angiography. A total of 49 consecutive subjects were studied. Patients under continuous ECG and 2D-Echo monitoring underwent standard dobutamine infusion at increasing doses to a diagnostic end-point. Tc99m Sestamibi was administered at the peak of the dobutamine effect. With this approach, 35 patients were identified correctly by 2D-Echo (Sensitivity = 60.1%; Specificity = 83.3%; Agreement = 71.4%; k = 0.43). Perfusion imaging with Tc99m Sestamibi resulted in correctly identifying 41 patients (Sensitivity = 83%; Specificity = 84%; Agreement = 83.6%; k = 0.67). Combining information obtained from the two tests resulted in increased specificity (92%) and decreased sensitivity (64%). Simultaneous assessment of perfusion and function with Tc99m Sestamibi and 2D-Echo imaging during dobutamine administration is easily performed without added risk or discomfort to the patient. Tc99m Sestamibi appeared to be slightly superior to 2D-Echo for the detection of CAD in this population, but the difference does not reach conventional statistical significance. The combined use of the two independent tests did not substantially improve the diagnostic accuracy of each method.

Adult↗

PubMed1989

[Diagnostic value of Q wave changes during the exercise test. Review of the literature and personal experience].

UNLABELLED: To test if a low Q wave voltage and its faulty increase after exercise is an additional sign of myocardial ischemia, 64 pts with no previous myocardial infarction, bundle branch block or left ventricular hypertrophy were studied by a treadmill test and coronary angiography. Nineteen had single vessel disease (SVD), 21 double vessel disease (DVD), 4 triple vessel disease (TVD) and 20 normal coronary arteries. Sensitivity (SENS), specificity (SPEC) and predictive value (P) of Q wave changes have resulted as follows: 84%, 55%, 80.4%, respectively, compared to 79.5%, 75%, 87.5% of ST modifications associated or not with angina. The SENS of Q wave changes was 72% in SVD and 92% in multivessel disease (p less than 0.05). In 68% of our pts ST and Q wave changes gave concordant results and their combination increased SENS, SPEC, PV to 90.1%, 80%, 90.3%. IN CONCLUSION: Q wave analysis can provide further evidence of myocardial ischemia and can increase SENS, SPEC of stress test. In our experience Q wave is a more sensitive finding than ST depression in multivessel disease.

Coronary Disease↗

PubMed1988

Primary hyperparathyroidism and angina pectoris.

We report the case of a 50-year-old female suffering from angina pectoris with a positive exercise test and normal coronary arteriography. Nifedipine relieved the angina. Laboratory tests demonstrated hypercalcaemia and led to a diagnosis of parathyroid adenoma. Surgical removal of the adenoma resulted in normalization of calcaemia and, during 4-year follow-up, she has had no angina. Two exercise tests in this period were negative.

Adenoma↗