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P Ballo

Publications and source records attributed to P Ballo.

6 recordsLinked to original sources
PubMed2002

Noninvasive tests for risk stratification in major vascular surgery.

BACKGROUND: The predictive values of noninvasive tests versus perioperative cardiac events in patients undergoing major vascular surgery has not been definitively established. PATIENTS AND METHODS: According to clinical markers and left ventricular function at rest, 188 patients were assigned to the following groups: 40 low, 115 moderate and 33 high risk. They were then randomly submitted to dipyridamole (n = 64), dobutamine (n = 63) stress echocardiography and dipyridamole perfusion scintigraphy (n = 61). RESULTS: No events were observed in low-risk patients, whereas 12 (10.4%) and 8 (24%) events in moderate- and high-risk categories occurred, respectively. Only the high-risk category, as a predictive variable, was significantly related to the onset of cardiac complications (p < 0.05). A positive dipyridamole/dobutamine stress test was related to cardiac events, but multivariate analysis showed that only severity and extent of ischemia were the best predictors of events (p < 0.01 for dipyridamole and p < 0.005 for dobutamine). The presence of reversible, but not fixed, perfusion defects at scintigraphy was significantly related to perioperative events; at multivariate analysis, only > 3 reversible perfusion defects represented a strong predictor of events (p < 0.05). CONCLUSIONS: Among subjects undergoing major vascular surgery, severity and extent of ischemia during dipyridamole/dobutamine stress echocardiography and presence of > 3 reversible perfusion defects are strong predictors of cardiac events, particularly in moderate-risk category of patients.

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PubMed2001

Prognostic value of dipyridamole stress echocardiography in hypertensive patients with left ventricular hypertrophy, chest pain and resting electrocardiographic repolarization abnormalities.

BACKGROUND: Hypertension is a major cardiovascular risk factor in the development of coronary artery disease (CAD); therefore, evaluating the presence of CAD is a primary clinical goal. However, the noninvasive tests that are commonly used have poor diagnostic specificity, particularly in patients with left ventricular hypertrophy. OBJECTIVES: To assess the prognostic value of dipyridamole stress echocardiography (DET) for ischemic events in a subset of patients with hypertension with left ventricular hypertrophy, chest pain and resting electrocardiographic repolarization abnormalities. PATIENTS AND METHODS: Eighty-two patients (48 men and 34 women; average age 65+/-7.2 years with left ventricular hypertrophy documented echocardiographically (left ventricular mass index greater than 50 g/h(2.7)), and resting ST segment shift of 0.1 mV or more from baseline at 80 ms after J point in at least two contiguous leads, were submitted to DET according to high-dosage protocol and coadministered with atropine. RESULTS: The follow-up period was 25.11+/-8.3 months. The stress test produced positive results in 30 patients (36.5%); 16 (53%) and three (5%) cardiac events occurred in positive and negative stress test groups, respectively. At multivariate analysis, only positive DET response (P=0.000002), left ventricular mass index (P=0.028) and a family history of CAD (P=0.037) were independent predictors. The two-year event-free survival rates were 95% and 47% (log-rank 21.093, P=0.00001) for negative and positive stress test results, respectively. CONCLUSIONS: DET is a useful tool in the prognostic assessment of coronary events in this particular subgroup of patients with hypertension.

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PubMed1995

Oscillations in a chloroplast suspension system.

Results of experimental and theoretical study of a photosynthetic system presented with rather complicated temporal behaviour are shown. Experimental results are comparable with those obtained previously by using the electrical method, and thus provide a support to the applicability of the more convenient spectrophotometric method. A possible explanation of a multimode nature of the oscillations observed is presented.

Chloroplasts↗