PubMed Health⌕ Search

Biomedical subjects

D Lasorda

Publications and source records attributed to D Lasorda.

5 recordsLinked to original sources
PubMed1999

Hemodynamic effects of new intra-aortic balloon counterpulsation timing methods in patients: a multicenter evaluation.

BACKGROUND: To test whether later intra-aortic balloon pump (IABP) deflation approaching or simultaneous with left ventricular ejection would improve hemodynamics and myocardial efficiency with the use of new balloon deflation methods, 4 IABP timing techniques were evaluated in 43 patients. METHODS AND RESULTS: Later balloon deflation produced significantly greater percentage changes in mean aortic pressure (6% vs 1%), systolic pressure time index (-27% vs -20%), diastolic pressure time index (35% vs 19%), and the systolic pressure-time index/diastolic pressure-time index ratio (97% vs 51%), respectively. However, these changes increased peak systolic pressure (-15% vs -11%). Cardiac output and stroke volume indexes were not significantly altered over the 4 settings. CONCLUSIONS: These data suggest that systemic hemodynamics and myocardial efficiency may be improved by later balloon deflation approaching left ventricular ejection in comparison to conventional IABP timing.

Adult↗
PubMed1997

Correlations between coronary flow reserve measured with a Doppler guide wire and treadmill exercise testing.

We compared exercise test results to a physiologic depiction of stenosis severity, coronary flow reserve (CFR), measured with a Doppler guide wire in 35 patients with single-vessel coronary disease. Group 1 (n = 21) had abnormal CFR, and group 2 (n = 14) had normal CFR. In group 1, 14 of 21 had ST-segment depression versus 3 of 14 in group 2 (p < 0.01). Exercise treadmill time (Bruce protocol) was normalized to the age- and sex-predicted time. Exercise time and normalized exercise time were less in group 1 (5.6 +/- 2.3 vs 9.9 +/- 1.8 min and 0.82 +/- 0.32 vs 1.25 +/- 0.23, p < 0.00001). Having either ST-segment depression or a normalized exercise time <1 during exercise had a 95% sensitivity, 71% specificity, and 86% predictive accuracy in identifying abnormal CFR. Coronary stenoses and minimal lumen diameter were similar in groups 1 and 2. By using stepwise logistical regression analysis, exercise time and ST-segment depression predicted CFR with a total r2 of 0.51. Minimal lumen diameter did not significantly add to the model. Exercise test variables, ST-segment depression, and exercise time are predictive of the physiologic significance of coronary lesions.

Aged↗
PubMed1994

Intracoronary Doppler guide wire versus stress single-photon emission computed tomographic thallium-201 imaging in assessment of intermediate coronary stenoses.

OBJECTIVES: The purpose of this study was to compare measures of coronary flow reserve by an intracoronary Doppler guide wire with results of stress single-photon emission computed tomographic (SPECT) thallium-201 imaging in patients with intermediate coronary artery disease (40% to 70% stenosis). BACKGROUND: Visual assessment of the coronary arteriogram as a means of predicting the physiologic significance of intermediate coronary stenoses is inaccurate. Coronary flow reserve is a reliable marker of the functional importance of a coronary lesion. The recent development of an intracoronary Doppler guide wire permits routine assessment of coronary flow reserve distal to coronary artery stenoses. METHODS: We prospectively evaluated coronary flow reserve in 30 subjects with intermediate stenoses using an intracoronary Doppler guide wire during elective coronary angiography. Patients subsequently underwent stress SPECT thallium-201 testing, and the blinded interpretations were correlated. Coronary flow reserve in a control group with normal coronary arteries classified our sample into group 1 (abnormal flow reserve, < 2.0) and group 2 (normal flow reserve, > or = 2.0). RESULTS: As defined, the coronary flow reserve of 16 vessels in group 1 was diminished in comparison to that of 19 vessels in group 2 (p = 0.0001). Qualitative and quantitative analysis of stress SPECT thallium-201 images confirmed perfusion defects in 15 of 16 vascular territories in group 1 in contrast to 1 of 19 regions in group 2. The sensitivity, specificity and overall predictive accuracy of Doppler-determined coronary flow reserve for stress SPECT thallium-201 results were 94%, 95% and 94%, respectively. CONCLUSIONS: In appropriately selected patients with intermediate coronary artery stenoses, Doppler guide wire determination of lesion significance provides equivalent data to those acquired by stress SPECT thallium-201 imaging.

Aged↗