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Rollo P Villareal

Publications and source records attributed to Rollo P Villareal.

7 recordsLinked to original sources
PubMed2004

Postoperative atrial fibrillation and mortality after coronary artery bypass surgery.

OBJECTIVES: We sought to determine if the occurrence of postoperative atrial fibrillation (AF) affects early or late mortality following coronary artery bypass surgery (CABG). BACKGROUND: Atrial fibrillation is the most common arrhythmia seen following CABG. METHODS: The Texas Heart Institute Cardiovascular Research Database was used to identify all patients that developed AF after isolated initial CABG from January 1993 to December 1999 (n = 994). This population was compared with patients who underwent CABG during the same period but did not develop AF (n = 5,481). In-hospital end points were adjusted using logistic regression models to account for baseline differences. Long-term survival was evaluated using a retrospective cohort design, where Cox proportional hazards methods were used to adjust for baseline differences, and with case-matched populations (n = 390, 195 per arm). RESULTS: Atrial fibrillation was diagnosed in 16% of the population. Postoperative AF was associated with greater in-hospital mortality (odds ratio [OR] 1.7, p = 0.0001), more strokes (OR 2.02, p = 0.001), prolonged hospital stays (14 vs. 10 days, p < 0.0001), and a reduced incidence of myocardial infarction (OR 0.62, p = 0.01). At four to five years, survival was worse in patients who developed postoperative AF (74% vs. 87%, p < 0.0001 in the retrospective cohort; 80% vs. 93%, p = 0.003 in the case-matched population). On multivariate analysis, postoperative AF was an independent predictor of long-term mortality (adjusted OR 1.5, p < 0.001 in the retrospective cohort; OR 3.4, p = 0.0018 in the case-matched population). CONCLUSIONS: The occurrence of AF following CABG identifies a subset of patients who have a reduced survival probability following CABG. The impact of various strategies, such as antiarrhythmics and warfarin, aimed at reducing AF and its complications deserves further study.

Aged↗
PubMed2003

Inappropriate shock delivery and biventricular pacing cardiac defibrillators.

In the United States, physicians adapt currently available defibrillators to accommodate leads for biventricular pacing in those congestive heart failure patients who might benefit from cardiac resynchronization and who are additionally at risk for sudden cardiac death. The adaptation of the lead system of available defibrillators to also allow them to function as biventricular pacemakers presents occasions in which inappropriate shocks are delivered due to double counting of the right and left ventricular depolarizations by the implantable cardiac defibrillator. We reviewed a series of inappropriate shock deliveries that occurred after the implantation of biventricular pacing cardiac defibrillators at our institution; all of these shocks were related to ventricular double counting. Each had different underlying causes and management strategies. Complications such as these emphasize the importance of attentiveness to ventricular channel electrograms and to device sensing with the use of biventricular pacing cardiac defibrillators. In addition, a thorough working knowledge of pacemaker and defibrillator operation is essential for the prediction and correction of inappropriate therapies.

Aged↗
PubMed2002

Heart rate variability and cardiovascular mortality.

The autonomic nervous system plays a major role in affecting the cardiac milieu and promoting malignant ventricular activity. The measurement of heart rate variability (HRV) is a noninvasive tool for assessing the status of the autonomic nervous system. A depressed HRV among post-myocardial infarction patients is a well-established risk factor for arrhythmic death. A reduced HRV has also been used to identify diabetic patients with autonomic neuropathy. This paper presents recent developments in the use of HRV, focusing on further refinement and validation of the use of both linear and nonlinear dynamics for sudden death prognostication, evaluation of the effect of specific pharmacologic agents on HRV, and assessment of HRV in health and in specific disease states that have been associated with an increased mortality risk.

Autonomic Nervous System↗
PubMed2002

Coronary artery bypass surgery versus coronary stenting: risk-adjusted survival rates in 5,619 patients.

We used the Texas Heart Institute Cardiovascular Research Database to retrospectively identify patients who had undergone their 1st revascularization procedure with coronary artery bypass surgery (CABG; n=2,826) or coronary stenting (n=2,793) between January 1995 and December 1999. Patients were classified into 8 anatomic groups according to the number of diseased vessels and presence or absence of proximal left anterior descending coronary artery disease. Mortality rates were adjusted with proportional hazards methods to correct for baseline differences in severity of disease and comorbidity. We found that in-hospital mortality was significantly greater in patients undergoing CABG than in those undergoing stenting (3.6% vs 0.75%; adjusted OR 8.4; P < 0.0001). At a mean 2.5-year follow-up, risk-adjusted survival was equivalent (CABG 91%, stenting 95%; adjusted OR 1.26; P = 0.06). When subgroups matched for severity of disease were compared, no differences in risk-adjusted survival were seen. A survival advantage of stenting was noted in 3 categories of patients: those >65 years of age (OR 1.33, P = 0.049), those with non-insulin-requiring diabetes (OR 2.06, P = 0.002), and those with any noncoronary vascular disease (OR 1.59, P = 0.009). In this nonrandomized observational study, CABG had a higher periprocedural mortality rate than did percutaneous stenting. At 2.5 years, however, the survival advantage of stenting was no longer evident. These data suggest that there is no intermediate-term survival advantage of CABG over stenting in patients who have multivessel disease with lesions that can be treated percutaneously.

Aged↗
PubMed2002

Rapid ventricular tachycardias associated with cilostazol use.

A 92-year-old woman with normal systolic function had recently begun using the newly approved phosphodiesterase III inhibitor cilostazol when she was admitted with lower-extremity pain. Cilostazol is indicated for patients with intermittent claudication and contraindicated for patients with congestive heart failure. Two days after admission, the patient developed ventricular tachycardia. Cilostazol was discontinued, and shortly thereafter the ventricular tachycardia subsided. In this case, cilostazol was apparently an important predisposing factor for ventricular tachycardia.

Aged↗
PubMed2002

Magnetic resonance imaging of myocardial fibrosis in hypertrophic cardiomyopathy.

Myocardial fibrosis can occur in patients who have hypertrophic cardiomyopathy in the absence of epicardial coronary disease. In such patients, myocardial fibrosis has been linked to a poorer prognosis than in those without fibrosis. Gadolinium-DTPA delayed-enhancement magnetic resonance imaging (de-MRI) accurately identifies regions of myocardial fibrosis. We used de-MRI to screen for myocardial fibrosis in 8 patients with nonobstructive hypertrophic cardiomyopathy that had been diagnosed by 2-dimensional echocardiography. After localization of the heart and acquisition of electrocardiographically gated cine images, gadolinium-DTPA (0.2 mmol/kg) was administered to the patient. Fifteen minutes later, de-MRI images were obtained using a T1-weighted, inversion-recovery fast, low-angle shot sequence. Images were gated to end-diastole and obtained during a single breath-hold. The inversion time was modified iteratively to obtain maximal nulling of the signal from the ventricular myocardium. Regions of myocardium with abnormally high signals (>300% of remote normal myocardium) were designated as fibrotic. Eight patients with hypertrophic cardiomyopathy underwent de-MRI. The mean age was 52 years, the mean left ventricular mass was 201 grams, and the mean ejection fraction was 0.68. In the 6 patients with recent clinical deterioration, de-MRI showed clearly delineated areas of myocardial fibrosis; no such areas were seen in the 2 asymptomatic patients. We conclude that patients with symptomatic hypertrophic cardiomyopathy display regions of abnormal signal intensity on de-MRI that likely represent fibrosis. This technique may provide useful information in the evaluation of such patients and warrants further study.

Adult↗