Search PubMed⌕ Search

Biomedical subjects

U Deligonul

Publications and source records attributed to U Deligonul.

At least 73 records · Page 4Linked to original sources
PubMed1990

Ventricular arrhythmia due to intracoronary papaverine: analysis of QT intervals and coronary vasodilatory reserve.

Intracoronary papaverine commonly produces striking QT interval prolongation with rare but serious ventricular dysrhythmias reported. Because of 3 cases of severe papaverine-induced dysrhythmia in our laboratory, QT intervals and hemodynamic and intracoronary velocity data collected during intracoronary papaverine administration were retrospectively reviewed in 34 patients; 20 patients with angiographically normal coronary arteries (group 1) and 14 patients (group 2) before and (group 2) after single-vessel left coronary angioplasty. QT intervals increased from 394 +/- 44 to 464 +/- 73 msec, 414 +/- 47 to 504 +/- 95 msec, and 410 +/- 41 to 486 +/- 75 msec for groups 1 and 2 before and after angioplasty, respectively (all P less than 0.01). There was no correlation with hemodynamic, electrocardiographic, or coronary vasodilatory reserve responses and change in QTc interval. In the 3 index patients having significant papaverine-related arrhythmias, a baseline QT interval was prolonged (after prior papaverine exposure) in only 1 in association with torsade de pointes. These data indicate that QT interval prolongation after papaverine is a common occurrence, but that the production of ventricular dysrhythmia is probably idiosynchratic in origin. In view of these findings, we recommend that appropriate antiarrhythmic preparations be in place for patients receiving intracoronary papaverine.

Adult↗
PubMed1990

Early ambulation after 5 French diagnostic cardiac catheterization: results of a multicenter trial.

Because earlier ambulation and discharge after cardiac catheterization may result in the increased utilization of outpatient facilities, a prospective five center clinical pilot trial assessing the safety and outcome of early ambulation after routine left heart catheterization was performed in 287 patients. Catheterization routines at each clinical center were unchanged throughout the study. After the diagnostic catheterization using 5 French (F), preformed, large lumen catheters and arterial puncture compression (mean 15 min, range 5 to 52), 260 patients were ambulated by a physician at a mean time of 2.6 h (range 1.8 to 3.1) after catheterization. Follow-up examination or a phone call 24 to 72 h later was performed to assess late results. The mean age of the patients was 58 years (range 25 to 91); 166 (58%) were men. Left ventricular ejection fraction was 54 +/- 15%. One hundred twenty-seven patients (44%) received intravenous heparin (1,500 to 5,000 U as an intravenous bolus) and 136 (47%) received aspirin. Major complications included transient ischemic attack (one patient) and ventricular tachycardia requiring cardioversion during ventriculography (two patients). A small hematoma (less than 5.0 cm) after ambulation occurred early (from compression to standing) in 14 patients (5%; 9 received heparin, 8 were taking aspirin) and later (after standing to 72 h) in 9 patients (3%; 2 receiving heparin, 2 taking aspirin). Five patients with a hematoma had studies with a 6F sheath. No patient required surgical intervention for early or late hematoma. Only three patients (1%) needed a 7F or 8F catheter because of suboptimal 5F coronary angiography.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

Effects of diltiazem and nifedipine on systemic and coronary hemodynamics and ischemic responses during transient coronary artery occlusion in patients.

Diltiazem and nifedipine improve coronary blood flow and reduce peripheral determinants of myocardial oxygen demand through activation of similar but distinct cellular mechanisms. To identify differences during myocardial ischemia, systemic and coronary hemodynamics were measured continuously before and during brief periods of left anterior descending coronary balloon occlusion in 23 patients undergoing single-vessel angioplasty. Data were compared for two matched ischemic periods, one control and one "drug" period. In 13 patients, diltiazem, 10 mg (intravenous bolus with continuous 500 mg/min infusion), was given; in 10 patients, nifedipine, 10 mg sublingual, was given and after 15 minutes, ischemia was reinduced. Both drugs significantly reduced systolic and mean arterial pressure (for diltiazem, 108 +/- 15 to 93 +/- 10 mm Hg; and for nifedipine, 117 +/- 20 to 96 +/- 8 mm Hg, both p less than 0.01). Diltiazem significantly reduced heart rate-pressure product (with heart rate unchanged), while both drugs maintained the resting great vein blood flow (for diltiazem, 97 +/- 25 to 91 +/- 34 ml/min; for nifedipine, 115 +/- 49 to 98 +/- 58 ml/min, p = ns) with reduced arterial pressure. Coronary flow during occlusion was unchanged (for control versus diltiazem, 63 +/- 21 versus 59 +/- 14 ml/min; for nifedipine, 66 +/- 33 versus 73 +/- 38 ml/min, both p = ns). Neither drug improved collateral hemodynamics or resistance index during ischemia. Both diltiazem and nifedipine prolonged the time to ischemic ST segment alteration (for diltiazem, 27 +/- 10 to 40 +/- 16 seconds, p less than 0.05; for nifedipine, 24 +/- 14 to 38 +/- 14 seconds, p = ns) during transient coronary occlusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiography↗
PubMed1990

Use of coronary arteriography in the preoperative management of patients undergoing urgent repair of the thoracic aorta.

Noninvasive innovations have advanced the timing and precision of diagnosis of acute dissection or enlarging aortic aneurysm. However, the need to perform coronary arteriography prior to surgical repair in these patients remains a question for many clinicians. This retrospective 10-year (1978 to 1988) review examined data of 54 patients undergoing urgent surgical repair of thoracic aortic tear, aneurysm, or dissection in our institution. Results of coronary arteriography and clinical variables (history of coronary artery disease, electrocardiographic abnormalities, surgical procedures, and in-hospital mortality) were tabulated. Twenty-seven patients had type A aortic dissection and 27 patients had type B. Twenty-four patients had aortic dissection or tear (type A or B) due to motor vehicle trauma. In patients with type A, a history and/or electrocardiogram suggestive of coronary artery disease was present in 16, in whom cardiac catheterization was performed in five. None required coronary bypass surgery or died. In the 11 patients with no clinical history of coronary artery disease or electrocardiographic abnormalities, six had cardiac catheterization, none had coronary artery disease, two had coronary reimplantation, and six died. Only 1 of the 27 patients with type A dissection had a perioperative myocardial infarction (a patient with a clinical history of coronary artery disease who did not undergo cardiac catheterization). In patients undergoing type B aortic repair, 10 had a clinical history or electrocardiogram consistent with coronary artery disease but only one underwent cardiac catheterization and subsequent coronary artery bypass graft surgery for coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Effect of abruptly increased intrathoracic pressure on coronary blood flow velocity in patients.

To assess the effects of abruptly increased intrathoracic pressure on coronary blood flow, arterial pressure, heart rate, and intracoronary Doppler blood flow velocity were measured continuously during cough(s) and again during the four phases of the Valsalva maneuver in 14 patients. Coughing significantly increased the systolic pressure (137 +/- 25 to 176 +/- 30 mm Hg), diastolic pressure (72 +/- 10 to 84 +/- 18 mm Hg), and arterial pulse pressure (65 +/- 27 to 92 +/- 35 mm Hg), with no change in heart rate. The mean coronary flow velocity decreased (17 +/- 10 to 14 +/- 12 cm/sec, p less than 0.03). During the Valsalva maneuver, despite marked reduction in the mean arterial pressure during phase III (96 +/- 12 to 68 +/- 14 mm Hg, p less than 0.05), the reduction of coronary blood flow velocity did not achieve statistical significance. These data demonstrate that neither type of abrupt physiologic increase in intrathoracic pressure enhances coronary blood flow. Coughing does not improve coronary perfusion pressures or flow velocity, despite marked increases in arterial diastolic pressure. The Valsalva maneuver, for the most part, does not significantly alter coronary blood flow velocity.

Blood Flow Velocity↗
PubMed1990

Coronary morphologic and clinical determinants of procedural outcome with angioplasty for multivessel coronary disease. Implications for patient selection. Multivessel Angioplasty Prognosis Study Group.

To assess the likelihood of procedural success in patients with multivessel coronary disease undergoing percutaneous coronary angioplasty, 350 consecutive patients (1,100 stenoses) from four clinical sites were evaluated. Eighteen variables characterizing the severity and morphology of each stenosis and 18 patient-related variables were assessed at a core angiographic laboratory and at the clinical sites. Most patients had Canadian Cardiovascular Society class III or IV angina (72%) and two-vessel coronary disease (78%). Left ventricular function was generally well preserved (mean ejection fraction, 58 +/- 12%; range, 18-85%) and 1.9 +/- 1.0 stenoses per patient had attempted percutaneous coronary angioplasty. Procedural success (less than or equal to 50% final diameter stenosis in one or more stenoses and no major ischemic complications) was achieved in 290 patients (82.8%), and an additional nine patients (2.6%) had a reduction in diameter stenosis by 20% or more with a final diameter stenosis 51-60% and were without major complications. Major ischemic complications (death, myocardial infarction, or emergency bypass surgery) occurred in 30 patients (8.6%). In-hospital mortality was 1.1%. Stepwise regression analysis determined that a modified American College of Cardiology/American Heart Association Task Force (ACC/AHA) classification of the primary target stenosis (with type B prospectively divided into type B1 [one type B characteristic] and type B2 [greater than or equal to two type B characteristics]) and the presence of diabetes mellitus were the only variables independently predictive of procedural outcome (target stenosis modified ACC/AHA score; p less than 0.001 for both success and complications; diabetes mellitus: p = 0.003 for success and p = 0.016 for complications). Analysis of success and complications on a per stenosis dilated basis showed, for type A stenoses, a 92% success and a 2% complication rate; for type B1 stenoses, an 84% success and a 4% complication rate; for type B2 stenoses, a 76% success and a 10% complication rate; and for type C stenoses, a 61% success and a 21% complication rate. The subdivision into types B1 and B2 provided significantly more information in this clinically important intermediate risk group than did the standard ACC/AHA scheme. The stenosis characteristics of chronic total occlusion, high grade (80-99% diameter) stenosis, stenosis bend of more than 60 degrees, and excessive tortuosity were particularly predictive of adverse procedural outcome. This improved scheme may improve clinical decision making and provide a framework on which to base meaningful subgroup analysis in randomized trials assessing the efficacy of percutaneous coronary angioplasty.

Angiography↗
PubMed1989

Immediate and short-term effects of aortic balloon valvuloplasty on left ventricular diastolic function and filling in humans.

The effect of aortic balloon valvuloplasty on left ventricular diastolic function and filling was investigated in 44 adult patients with severe aortic stenosis. Two-dimensional and Doppler echocardiography was performed in all patients before and 24 h after valvuloplasty. In 19 patients (short-term group) repeat studies were performed at 3 (n = 2) and 6 (n = 17) months. Left ventricular relaxation, chamber stiffness and filling were assessed in 16 patients (immediate post-valvuloplasty group) before and immediately after valvuloplasty by simultaneous micromanometer left ventricular pressure tracings and echocardiograms. Immediately after valvuloplasty, relaxation was slightly impaired in the immediate post-valvuloplasty group, as reflected by the isovolumic relaxation time constant (56 +/- 26 to 68 +/- 39 ms; p less than 0.01) and maximal negative dP/dt (2,063 +/- 640 to 1,767 +/- 495 mm Hg/s; p less than 0.001). The chamber stiffness constants and diastolic filling dynamics were unchanged immediately after valvuloplasty. Twenty-four hours after valvuloplasty, patients without mitral regurgitation (n = 24) showed increases in the peak early filling velocity (72 +/- 31 to 83 +/- 28 cm/s; p less than 0.05) and peak early to atrial filling velocity ratio (0.8 +/- 0.6 to 1.0 +/- 0.7; p less than 0.05). However, in patients with mitral regurgitation (n = 20), the diastolic filling dynamics were not significantly changed. In the short-term group at the 3 to 6 month follow-up period, patients without mitral regurgitation (n = 12) showed striking increases compared with pre-valvuloplasty values in the peak early filling velocity (66 +/- 21 to 93 +/- 31 cm/s; p less than 0.02), peak early to atrial filling velocity ratio (0.6 +/- 0.2 to 0.9 +/- 0.4; p less than 0.02) and early time-velocity integral (9 +/- 4 to 16 +/- 6 cm; p less than 0.002). In patients with mitral regurgitation (n = 7) decreases occurred in the peak early filling velocity (123 +/- 32 to 106 +/- 28 cm/s; p less than 0.05) and peak early to atrial filling velocity ratio (1.5 +/- 0.7 to 1.1 +/- 0.6; p less than 0.05). Functional class in hospital improved after valvuloplasty (3.1 +/- 1.0 to 2.6 +/- 0.9; p less than 0.001) and correlated modestly with the percent decrease in Doppler-derived peak gradient (rs = 0.41, p less than 0.02) and mean gradient (rs = 0.36, p less than 0.05), but did not correlate with changes in aortic valve area, left ventricular ejection fraction or diastolic filling variables.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗
PubMed1989

Hemodynamic and echocardiographic assessment of the effects of diltiazem during transient occlusion of the left anterior descending coronary artery during percutaneous transluminal coronary angioplasty.

The effects of diltiazem during transient myocardial ischemia were studied in 17 patients (age 58 +/- 11 years, 12 men, 5 women) undergoing 1-vessel left anterior descending percutaneous transluminal coronary angioplasty (PTCA). After hemodynamic, echocardiographic and electrocardiographic data were obtained during the control ischemic periods, diltiazem (10 mg intravenous bolus with 500 micrograms/min infusion) was given and 15 minutes later ischemia reinduced. Diltiazem reduced mean arterial pressure (113 +/- 16 to 95 +/- 15 mm Hg, p less than 0.05) and heart rate-pressure product (p less than 0.05) with no change in heart rate, pulmonary pressures or coronary (sinus, thermodilution technique) blood flow at rest. After diltiazem, times to ischemia-induced 1.0 mm ST-segment elevation (28 +/- 10 to 42 +/- 17 seconds, p less than 0.05) and new left ventricular wall motion abnormalities (by 2-dimensional echocardiography, 24 +/- 8 to 36 +/- 12 seconds, p less than 0.001) were prolonged without significant augmentation of great cardiac vein flow during coronary occlusion. Left ventricular (LV) ejection fraction decreased from 51 +/- 7 to 41 +/- 12% (p less than 0.05) during control ischemia, but declined less after diltiazem (54 +/- 12 to 47 +/- 14%, difference not significant; 47 +/- 14 vs 41 +/- 12%, p less than 0.01). Diltiazem can attenuate, but not abolish, some of the effects of myocardial ischemia on LV function during transient coronary artery occlusion. These data support the use of diltiazem as a beneficial adjunct that may be used acutely and safely during routine PTCA.

Adult↗
PubMed1989

Prognostic significance of silent myocardial ischemia detected by early treadmill exercise after coronary angioplasty.

Three hundred ninety patients who had successful coronary angioplasty were studied by treadmill exercise testing to determine the incidence and prognostic importance of silent and symptomatic myocardial ischemia in this patient subset. All patients were followed for an average of 11 months. During exercise, 81 patients (20%) had abnormal exercise-induced ST-segment depression without chest pain (group 1). Twenty patients (5%) had chest pain without ST changes (group 2). Twenty-one patients (5%) had both exercise-induced chest pain and ST-T-segment depression (group 3) and 268 patients (70%) had a normal exercise test with no chest pain (group 4). The groups were similar with respect to age, sex, history of previous myocardial infarct and previous coronary bypass surgery. Group 4 included more patients with complete revascularization. Mutually exclusive cardiac events were defined as cardiac death, nonfatal myocardial infarction, class III angina and additional revascularization (coronary angioplasty, coronary artery bypass surgery). The cardiac event rate in groups 1, 2 and 3 were significantly higher than in group 4 (40, 45 and 43 vs 22%; p = 0.001). There were 4 cardiac deaths and 4 nonfatal myocardial infarctions in group 1 compared to 2 cardiac deaths and 3 nonfatal myocardial infarctions in group 4 (p = 0.03 and 0.05, respectively). The event rates in groups 1, 2 and 3 patients with multivessel disease were significantly greater than in group 4 (44, 60 and 47 vs 22%; p = 0.002). Thus, exercise-induced myocardial ischemic episodes, both symptomatic and silent, early after coronary angioplasty are predictive of an unfavorable prognosis and serious cardiac events, particularly in patients with multivessel disease and incomplete revascularization.

Aged↗
PubMed1989

Impaired coronary vasodilator reserve in the immediate postcoronary angioplasty period: analysis of coronary artery flow velocity indexes and regional cardiac venous efflux.

The ratio of peak hyperemic/basal mean coronary flow velocity, an index of coronary vasodilator reserve, immediately after coronary angioplasty normalizes in less than 50% of patients. To evaluate other indexes of coronary vasodilator capacity, both intracoronary arterial velocity and cardiac venous efflux were measured at rest and during vasodilator-induced coronary hyperemia (intracoronary nitroglycerin and papaverine) before and after angioplasty in 27 patients; 17 patients had measurements of intracoronary velocity alone and 10 had thermodilution measurements of great cardiac vein flow. Coronary flow velocity responses were also measured in 6 angiographically normal segments in patients undergoing angioplasty and in 10 normal left coronary artery segments in patients with normal coronary arteries or isolated right coronary artery disease. Despite significant angiographic (72 +/- 12 to 23 +/- 11% diameter narrowing) and hemodynamic (49 +/- 12 to 19 +/- 12 mm Hg aortocoronary gradient) improvement, coronary vasodilator reserve ratios for both arterial velocity and venous flow after angioplasty were only minimally affected. Angioplasty did not significantly increase rest coronary vein flow or artery flow velocities, but did result in significantly higher papaverine responses after angioplasty. Mean and phasic coronary velocity, diastolic coronary flow velocity integral and measured great cardiac vein flow ratios were significantly lower when compared with those in 16 angiographically normal coronary artery segments. These data indicate that maximal hyperemic coronary flow velocity is increased after angioplasty, but the reserve ratios, calculated by any of several flow velocity indexes, remain minimally improved. Angiographic correlations (percent coronary diameter, absolute diameter or cross-sectional area) with variables of coronary blood flow or velocity suggest that no single variable is useful in assessing angioplasty results. However, postangioplasty arterial mean velocity and diastolic flow velocity integral are nearly normalized in most patients, whereas relative changes remain attenuated. These findings are important in studies assessing coronary vasomotor responses in patients with atherosclerotic coronary disease, especially after angioplasty.

Adult↗