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P Guiteras

Publications and source records attributed to P Guiteras.

9 recordsLinked to original sources

Five years of angiographic and clinical follow-up after successful percutaneous transluminal coronary angioplasty.

The first 67 consecutive patients (77 lesions) who underwent successful coronary angioplasty (PTCA) at our hospital were clinically followed with serial exercise testing over a 5-year (4 to 7) observation period. Two sequential angiographic controls were performed 6.9 +/- 4.6 (64 patients) and 49.5 +/- 21.6 (42 patients) months after PTCA. The 5-year risk of cardiac death was 8%, of myocardial infarction 2%, or coronary artery bypass grafting 16% and of repeat PTCA 8%. At 5 years, 67% of the patients remain asymptomatic. Restenosis greater than or equal to 70% diameter was observed within the first year after PTCA in 30% of the patients. Progression of coronary artery disease (CAD) was observed in 13 patients (20%). In the first angiographic control, CAD progression was 4% (3/77) in dilated and 3% (3/115) in non-dilated arteries (ns). In the second angiographic control, it was 7% (3/45) and 10% (8/81), respectively (ns). Thus good clinical and angiographic results are still observed after 5 years. Restenosis is an early, self-limited, time-restricted phenomenon that occurs in 30% of patients. Angioplasty does not appear to accelerate CAD progression.

Angina Pectoris

Prevention of aortocoronary vein-graft attrition with low-dose aspirin and triflusal, both associated with dipyridamole: a randomized, double-blind, placebo-controlled trial.

A randomized, double-blind, placebo-controlled trial was performed in 209 patients to evaluate the efficacy of a low dose of aspirin plus dipyridamole or that of a new antiplatelet agent (triflusal) plus dipyridamole in the prevention of aortocoronary vein-graft occlusion. An angiographic control performed in 161 patients 9 days after surgery showed no significant differences between groups, but a new control on 138 of those patients 6 months later did show significant linear trends towards fewer distal anastomosis occlusions (P = 0.027) from the placebo (24%, 22/91) to the aspirin (16%, 17/106) and to the trifusal groups (12%, 10/86), and towards fewer new occlusions (P = 0.056) from 12% (9/78) to 10% (10/99) and to 2.6% (2/78), respectively, in the same groups. A multivariate logistic regression model, used to determine the effect of 33 variables on distal anastomosis occlusion at 6 months control, demonstrated that diameter of distal bed (P = 0.006), moderately to severely atherosclerotic distal bed (P = 0.003) and the interactions between poor distal bed and triflusal (P = 0.005) were independent predictors of occlusion. Thus, triflusal plus dipyridamole appeared superior to low-dose aspirin plus dipyridamole in the prevention of vein-graft occlusion, independently of coronary and vein-graft determinants of occlusion.

Adult

Count-based scintigraphic method to calculate ventricular volumes in children: in vitro and clinical validation.

A "phantom" was used to validate 1) estimates of different depths of a constant radioactivity source, and 2) the calculation of different volumes using a constant depth and different attenuation coefficients. Using data from this in vitro study, scintigraphic estimates of right ventricular volume and ejection fraction were compared with those obtained by cineangiography in 36 children with either a normal right ventricle or various right ventricular diseases. The static program accurately estimates the distance from the radiation source to the collimator surface (r = 0.99). Radionuclide count methods best predict "phantom" volumes using attenuation coefficients between 0.11(-1) and 0.13(-1) cm. A coefficient of 0.10(-1) underestimates, whereas 0.15(-1) cm grossly overestimates actual volumes. In vivo data were therefore analyzed using an attenuation coefficient of 0.11(-1) with right ventricular counts corrected using either right ventricular or left ventricular background. Closest agreement between scintigraphic and cineangiographic volumes was obtained using right ventricular background, although end-diastolic volumes larger than 100 ml were substantially underestimated. On the basis of this study, the use of two different attenuation coefficients is suggested: the smaller 0.11(-1) cm to calculate end-systolic and end-diastolic volumes and the larger 0.15(-1) cm for volumes greater than 100 ml.

Adolescent

Diagnostic accuracy of exercise ECG lead systems in clinical subsets of women.

The diagnostic accuracy of 14-lead exercise electrocardiography was evaluated in 112 women who had no history of myocardial infarction and underwent coronary angiography. The sensitivity of ST-segment displacement of 0.1 mV or more in any of 14 ECG leads was 0.79 for coronary artery stenosis of at least 70%; the specificity was 0.66. Results were similar using bipolar ECG leads CC5 and CM5 or 11 standard ECG leads. The ST-segment shifts that occurred only during exercise were associated with a 77% false-positive rate (10 of 13). Downsloping ST-segment depression did not provide more diagnostic information than horizontal ST-segment depression in the three clinical subsets of women. In women with typical angina pectoris, ST-segment depression of at least 0.15 mV for 0.08 second after the J point or a final treadmill time less than 360 seconds was predictive of proximal left or multivessel coronary artery disease. In the women with probable angina or nonspecific chest pain, this finding was not of diagnostic value. ST-segment elevation of 0.1 mV or more in leads V1-2 or a VL predicted proximal stenosis of at lest 80% in the left anterior descending coronary artery in all six women with typical angina pectoris. Maximal exercise testing in women with typical angina provides important diagnostic information when 11 standard ECG leads are recorded. In women with probable angina or nonspecific chest pain, diagnostic exercise testing is less useful and bipolar leads CC5 and CM5 are sufficient for most clinical purposes.

Adult