Phillip J Habib

Effects of Bariatric Surgery on Inflammatory, Functional and Structural Markers of Coronary Atherosclerosis

This study was designed to assess the effects of bariatric weight loss surgery on structural, functional, and inflammatory markers of coronary atherosclerosis. Obesity is a worldwide epidemic and an independent risk factor for coronary atherosclerosis. It remains unclear whether surgically induced weight loss reduces cardiovascular risk. This prospective study enrolled 50 consecutive subjects with morbid obesity who underwent Roux-en-Y gastric bypass surgery (GBS) after failed attempts at medical weight loss. Subjects were recruited through a comprehensive weight loss center affiliated with an academic tertiary care hospital. All subjects had body mass indexes > or =40 kg/m(2) or body mass indexes of 35 to 40 kg/m(2) with > or =2 co-morbid obesity-related conditions. Markers of coronary atherosclerosis, including brachial artery flow-mediated dilation, carotid intima-media thickness, and high-sensitivity C-reactive protein, were measured before GBS and 6, 12, and 24 months after GBS. There were statistically significant improvements in all measured markers of coronary atherosclerosis after GBS. The mean body mass index decreased from 47 to 29.5 kg/m(2) at 24 months (p <0.001), the mean carotid intima-media thickness regressed from 0.84 to 0.50 mm at 24 months (p <0.001), mean flow-mediated dilation improved from 6.0% to 14.9% at 24 months (p <0.05), and mean high-sensitivity C-reactive protein decreased from 1.23 to 0.65 mg/dl at 6 months (p <0.001) and to 0.35 mg/dl at 24 months (p <0.001). In conclusion, GBS results in significant improvements in inflammatory, structural, and functional markers of coronary atherosclerosis.

The Relationship of Echocardiographic Dyssynchrony to Long-Term Survival Following Cardiac Resynchronization Therapy

Background— The ability of echocardiographic dyssynchrony to predict response to cardiac resynchronization therapy (CRT) has been unclear. Methods and Results— A prospective, longitudinal study was designed with predefined dyssynchrony indexes and outcome variables to test the hypothesis that baseline dyssynchrony is associated with long-term survival after CRT. We studied 229 consecutive class III to IV heart failure patients with ejection fraction ≤35% and QRS duration ≥120 milliseconds for CRT. Dyssynchrony before CRT was defined as tissue Doppler velocity opposing-wall delay ≥65 milliseconds, 12-site SD (Yu Index) ≥32 milliseconds, speckle tracking radial strain anteroseptal-to-posterior wall delay ≥130 milliseconds, or pulsed Doppler interventricular mechanical delay ≥40 milliseconds. Outcome was defined as freedom from death, heart transplantation, or left ventricular assist device implantation. Of 210 patients (89%) with dyssynchrony data available, there were 62 events: 47 deaths, 9 transplantations, and 6 left ventricular assist device implantations over 4 years. Event-free survival was associated with Yu Index (P=0.003), speckle tracking radial strain (P=0.003), and interventricular mechanical delay (P=0.019). When adjusted for confounding baseline variables of ischemic origin and QRS duration, Yu Index and radial strain dyssynchrony remained independently associated with outcome (P<0.05). Lack of radial dyssynchrony was particularly associated with unfavorable outcome in those with QRS duration of 120 to 150 milliseconds (P=0.002). Conclusions— The absence of echocardiographic dyssynchrony was associated with significantly less favorable event-free survival after CRT. Patients with narrower QRS duration who lacked dyssynchrony had the least favorable long-term outcome. These observations support the relationship of dyssynchrony and CRT response.

Response to Letter Regarding Article, “Relationship of Echocardiographic Dyssynchrony to Long-Term Survival After Cardiac Resynchronization Therapy”

Cardiac resynchronization therapy (CRT) has undoubtedly been of major benefit to many patients who have heart failure with wide QRS complexes, improving symptoms and survival. Unfortunately, the CRT nonresponder rate remains at about one third with the use of the current selection criteria. An appropriate goal is to better understand the factors related to nonresponse to improve patient care. In a recent study of 229 CRT patients, we reported that the absence of echocardiographic dyssynchrony was associated with a significantly less favorable event-free survival with the use of the combined end point of death, heart transplantation, or left ventricular assist device over 4 years after CRT.1 We appreciate the commendation from Fornwalt et al in their letter and …

SURVIVAL BENEFIT FROM CARDIAC RESYNCHRONIZATION THERAPY IN PATIENTS WITH BORDERLINE QRS DURATION

Background: Cardiac resynchronization therapy (CRT) has been shown to improve survival in patients with wide QRS. However, the effects of CRT on patients with borderline QRS duration (100 - 130ms) with echocardiographic dyssynchrony is not clear. Methods: To test the hypothesis that patients with borderline QRS and echo dyssynchrony have similar survival as patients with wide QRS after CRT, we studied 301 class III - IV heart failure patients with ejection fraction <35%. Borderline QRS patients had echo dyssynchrony assessed as: radial dyssynchrony by speckle tracking ≥130ms, opposing wall delay by tissue Doppler analysis ≥ 65ms or interventricular mechanical delay ≥ 40 ms. Survival free from transplant or left ventricular assist device after CRT was followed for 4 years. Results: Of the 301 patients, 192 had wide QRS 165±23 ms with age 66±12 yrs 55% ICM and 33% female; 63 had borderline QRS 116 ± 8ms with similar clinical features age 61±12 yrs 55% ICM, 28% female. Also, 46 patients (age 65 ± 15 years , QRS 170±31 ms , 53% ICM and 34% female) with attempted but failed CRT were used as a control. Both wide and borderline QRS patients had similar and significantly better event free survival after CRT than patients with failed CRT (p< 0.001). Conclusions: Patients with borderline QRS duration selected for CRT using echocardiographic dyssynchrony appear to have a similarly favorable event free survival as those with wide QRS and has potential clinical implications.

Relationship of Echocardiographic Dyssynchrony to Long-Term Survival After Cardiac Resynchronization TherapyClinical Perspective

Background— The ability of echocardiographic dyssynchrony to predict response to cardiac resynchronization therapy (CRT) has been unclear. Methods and Results— A prospective, longitudinal study was designed with predefined dyssynchrony indexes and outcome variables to test the hypothesis that baseline dyssynchrony is associated with long-term survival after CRT. We studied 229 consecutive class III to IV heart failure patients with ejection fraction ≤35% and QRS duration ≥120 milliseconds for CRT. Dyssynchrony before CRT was defined as tissue Doppler velocity opposing-wall delay ≥65 milliseconds, 12-site SD (Yu Index) ≥32 milliseconds, speckle tracking radial strain anteroseptal-to-posterior wall delay ≥130 milliseconds, or pulsed Doppler interventricular mechanical delay ≥40 milliseconds. Outcome was defined as freedom from death, heart transplantation, or left ventricular assist device implantation. Of 210 patients (89%) with dyssynchrony data available, there were 62 events: 47 deaths, 9 transplantations, and 6 left ventricular assist device implantations over 4 years. Event-free survival was associated with Yu Index (P=0.003), speckle tracking radial strain (P=0.003), and interventricular mechanical delay (P=0.019). When adjusted for confounding baseline variables of ischemic origin and QRS duration, Yu Index and radial strain dyssynchrony remained independently associated with outcome (P<0.05). Lack of radial dyssynchrony was particularly associated with unfavorable outcome in those with QRS duration of 120 to 150 milliseconds (P=0.002). Conclusions— The absence of echocardiographic dyssynchrony was associated with significantly less favorable event-free survival after CRT. Patients with narrower QRS duration who lacked dyssynchrony had the least favorable long-term outcome. These observations support the relationship of dyssynchrony and CRT response.