Heart rate variability (HRV) has been shown to be attenuated in patients with coronary artery disease (CAD) and may, therefore, be possibly used for the early detection of myocardial ischemia. We ...aimed to evaluate the diagnostic yield of a novel short-term HRV algorithm for the detection of myocardial ischemia in subjects without known CAD. We prospectively enrolled 450 subjects without known CAD who were referred to tertiary medical centers for exercise stress testing (EST) with single-photon emission computed tomography myocardial perfusion imaging (MPI). All subjects underwent 1-hour Holter testing with subsequent HRV analysis before EST with MPI. The diagnostic yield of HRV analysis was compared with EST, using MPI as the gold standard for the noninvasive detection of myocardial ischemia. All subjects had intermediate pretest probability for CAD. Mean age was 62 years, 38% were women, 51% had hypertension, and 25% diabetes mellitus. HRV analysis showed superior sensitivity (77%) compared with standard EST (27%). After multivariate adjustment, HRV was independently associated with an 8.4-fold (p <0.001) increased likelihood for the detection of myocardial ischemia by MPI, whereas EST did not show a statistically significant association with a positive MPI (odds ratio 2.1; p = 0.12). Of subjects who were referred for subsequent coronary angiography, the respective sensitivities of HRV and EST for the detection of significant CAD were 73% versus 26%. Our data suggest that HRV can be used as an important noninvasive technique for the detection of myocardial ischemia in subjects without known CAD, providing superior sensitivity to conventional EST in this population.
Objective The outcome of aortic valve replacement for patients with low gradient severe aortic stenosis and preserved ejection fraction has been debated. The aim of the present study was to evaluate ...the effect of aortic valve intervention on survival in that group. Methods A cohort of 416 consecutive patients with low gradient severe aortic stenosis (aortic valve area, ≤1 cm2 ; mean pressure gradient, <40 mm Hg) and preserved ejection fraction (≥50%) were identified from the Sheba Medical Center echocardiography database. Clinical data, aortic valve intervention, and death were recorded. Results During an average follow-up of 28 months, of 416 study patients (mean age, 76 ± 14 years, 42% men), 97 (23%) underwent aortic valve intervention and 140 (32%) died. Mantel-Byar analysis showed that the cumulative probability of survival was significantly greater after aortic valve intervention. Multivariate analysis revealed a 49% reduction in the risk of death after surgery ( P < .05). The survival benefit of aortic valve intervention was comparable with adjustment to older age, aortic valve area ≤ 0.8 cm2 , and a low (≤35 cm2 /m2 ) or normal (>35 cm2 /m2 ) stroke volume index. Conclusions Our findings suggest that aortic valve intervention is associated with improved survival among patients with low gradient severe aortic stenosis and preserved left ventricular function. The presence of either a low or normal stroke volume index did not affect the mortality benefit.
Abstract Background Transcatheter aortic valve implantation (TAVI) has become the treatment of choice for the symptomatic patients with aortic stenosis (AS) and high surgical risk. Pulmonary ...hypertension (PHTN) has been shown to be associated with worse early and late outcomes after aortic valve surgery. Data regarding the effect of TAVI on PHTN are limited. Methods and results We evaluated the characteristics and outcome of the patients with various degrees of systolic PHTN referred for TAVI. PHTN was defined as systolic pulmonary arterial pressure (SPAP) ≥50 mmHg as assessed by echocardiography. The patients with SPAP decrease after TAVI to below 50 mmHg were compared to the patients with persistent PHTN following TAVI. Of the 122 patients included in the present study, 49 (40%) patients had elevated SPAP prior to TAVI. This group of patients presented with smaller aortic valve areas, greater degrees of mitral or tricuspid regurgitation, lower left ventricular ejection fraction, and more prevalent chronic obstructive pulmonary disease (COPD) (all p < 0.05). Following TAVI, 57% of the patients with prior PHTN experienced a reduction in SPAP to below 50 mmHg. Multivariable analysis identified COPD to be the most powerful predictor for PHTN presence post-TAVI (hazard ratio 3.9, 95% confidence interval 1.5–9.9, p = 0.005). Post-TAVI PHTN (SPAP ≥50 mmHg) was associated with a 3.4-fold, independent, 2-year mortality risk ( p = 0.04). Conclusions Our data suggest that TAVI is associated with a significant reduction in pulmonary pressure in more than half of the patients with preprocedural PHTN. COPD identifies the patients with persistent PHTN after TAVI. Post-TAVI PHTN is associated with markedly worse outcome.
The aim of the present study was to evaluate whether assessment of stroke volume index (SVI) can be used to improve risk stratification among patients with low-gradient severe aortic stenosis and ...preserved ejection fraction (EF). Study population comprised 409 patients with aortic valve area ≤1.00 cm2 , mean gradient <40 mm Hg, and a normal EF (≥50%) who were followed up in a tertiary referral center from 2004 to 2012. Echocardiographic parameters and clinical data were collected. Multivariate Cox proportional hazards regression modeling was used to evaluate the association between SVI and the risk of all-cause mortality. Mean age of study patients was 78 ± 11 years, and 42% were men. The mean SVI was 39 ± 7 ml/m2 (tertile 1 = 32 ± 4 ml/m2 ; tertile 2 = 39 ± 1 ml/m2 ; tertile 3 = 47 ± 4 ml/m2 ). Multivariate analysis showed that the SVI was the most powerful echocardiographic parameter associated with long-term outcome: each 5 ml/m2 reduction in SVI was associated with a 20% increase in adjusted mortality risk (p = 0.01). Consistently, Kaplan-Meier analysis showed that the cumulative probability of survival during 3 years of follow-up was 60%, 72%, and 73% among patients in the low-, intermediate-, and high-SVI groups, respectively (p = 0.012). Our findings suggest that in patients with low-gradient severe aortic stenosis and preserved EF, there is a graded inverse relation between SVI and the risk of long-term mortality.
Abstract Objectives This study sought to examine whether imaging of the atrioventricular (AV) membranous septum (MS) by computed tomography (CT) can be used to identify patient-specific anatomic risk ...of high-degree AV block and permanent pacemaker (PPM) implantation before transcatheter aortic valve implantation (TAVI) with self-expandable valves. Background MS length represents an anatomic surrogate of the distance between the aortic annulus and the bundle of His and may therefore be inversely related to the risk of conduction system abnormalities after TAVI. Methods Seventy-three consecutive patients with severe aortic stenosis underwent contrast-enhanced CT before TAVI. The aortic annulus, aortic valve, and AV junction were assessed, and MS length was measured in the coronal view. Results In 13 patients (18%), high-degree AV block developed, and 21 patients (29%) received a PPM. Multivariable logistic regression analysis revealed MS length as the most powerful pre -procedural independent predictor of high-degree AV block (odds ratio OR: 1.35, 95% confidence interval CI: 1.1 to 1.7, p = 0.01) and PPM implantation (OR: 1.43, 95% CI: 1.1 to 1.8, p = 0.002). When taking into account pre- and post -procedural parameters, the difference between MS length and implantation depth emerged as the most powerful independent predictor of high-degree AV block (OR: 1.4, 95% CI: 1.2 to 1.7, p < 0.001), whereas the difference between MS length and implantation depth and calcification in the basal septum were the most powerful independent predictors of PPM implantation (OR: 1.39, 95% CI: 1.2 to 1.7, p < 0.001 and OR: 4.9, 95% CI: 1.2 to 20.5, p = 0.03; respectively). Conclusions Short MS, insufficient difference between MS length and implantation depth, and the presence of calcification in the basal septum, factors that may all facilitate mechanical compression of the conduction tissue by the implanted valve, predict conduction abnormalities after TAVI with self-expandable valves. CT assessment of membranous septal anatomy provides unique pre-procedural information about the patient-specific propensity for the risk of AV block.
Transcatheter aortic valve implantation (TAVI) is a novel treatment for high risk or inoperable patients with symptomatic severe aortic stenosis. However, significant atrioventricular (AV) conduction ...system abnormalities requiring permanent pacemaker (PPM) implantation might complicate this procedure. We used best subsets logistic regression analysis to identify the independent predictors for the development of high-degree AV block (HDAVB) among 70 patients who underwent TAVI at 3 referral centers in Israel from 2008 to 2010. The mean age of the study patients was 83 ± 4.6 years. Of the 70 patients, 28 (40%) developed AV conduction abnormalities requiring PPM implantation within 14 days (median 2) of the procedure. The indications for PPM implantation were HDAVB (n = 25), new-onset left bundle branch block with PR prolongation (n = 2), and slow atrial fibrillation (n = 1). Best subsets logistic regression analysis showed that, among the 15 prespecified clinical, electrocardiographic, and echocardiographic candidate risk factors, only right bundle branch block at baseline (odds ratio 43; p = 0.002) and deep valve implantation (<6 mm from the lower edge of the noncoronary cusp to the ventricular end of the prosthesis, odds ratio 22; p <0.001) were independently associated with the development of periprocedural HDAVB. At 3 months of follow-up, HDAVB was still present in 40% of the patients who received PPM implantation for this indication. In conclusion, 40% of the patients who undergo CoreValve TAVI require PPM implantation after the procedure, with most cases (36%) associated with the development of postprocedural HDAVB. Baseline conduction abnormalities (right bundle branch block) and deep valve implantation (>6 mm) independently predicted the development of HDAVB and the need for PPM implantation after CoreValve TAVI.
Long QT Syndrome Goldenberg, Ilan, MD; Moss, Arthur J., MD
Journal of the American College of Cardiology,
06/2008, Letnik:
51, Številka:
24
Journal Article
Recenzirano
Odprti dostop
Long QT Syndrome Ilan Goldenberg, Arthur J. Moss The hereditary long QT syndrome (LQTS) is an important cause of malignant ventricular arrhythmias and sudden cardiac death in young individuals with ...normal cardiac morphology. We provide an overview of major advances in the understanding of this genetic channelopathy, including molecular and genetic considerations, recommendations for diagnosis and risk stratification, and therapeutic considerations. Particular focus is placed on the importance of time-dependent and age-specific risk assessment in this population, as well as on recent advances in the understanding of the association between the biophysical function of the ion-channel mutation and the outcome of LQTS patients.
Elderly patients are underrepresented in clinical trials of device therapy.
To provide real-world data regarding outcomes associated with device-based therapy in a large cohort of elderly patients ...enrolled in the Israeli ICD Registry.
Between July 2010 and June 2012, a total of 2807 consecutive patients undergoing implanted cardioverter-defibrillator/cardiac resynchronization therapy-defibrillator (ICD/CRT-D) implantation were prospectively enrolled in the Israeli ICD Registry. For the present analysis, patients were categorized into 3 age groups: ≤60 years (n = 1378 49%), 61-75 years (n = 863 31%), and >75 years (n = 566 20%).
Elderly patients (>75 years of age) had more comorbid conditions and were more likely to undergo CRT-D implantation (all P < .01). However, the rate of device-related complications associated with surgical reinterventions at 1 year was <3% regardless of age (P = .70 for the comparison among the 3 age groups). Multivariate analysis showed that the risk of heart failure or death and of appropriate ICD therapy for ventricular arrhythmias was significantly increased with increasing age among patients who received an ICD. In contrast, the age-related increase in the risk of all end points was attenuated among patients who received CRT-D devices (all P values for age-by-device-type interactions are <.05).
In a real-world scenario, elderly patients (>75 years of age) comprise approximately 20% of the ICD/CRT-D recipients and experience a device reintervention rate similar to that of their younger counterparts. Our data suggest that the association between advanced age and adverse clinical outcomes is attenuated in elderly patients implanted with CRT-D devices.
Implantable cardioverter-defibrillators (ICDs) have become the mainstay of preventive measures for sudden cardiac death (SCD). However, there are limited data on rates of appropriate life-saving ICD ...shock therapies in contemporary real-life settings.
The purpose of the study was to evaluate the rate of appropriate life-saving ICD shock therapies in a contemporary registry.
The Israeli ICD Registry includes all implants and other ICD operative procedures nationwide. The present study comprises 2349 consecutive cases who were enrolled in the Registry and prospectively followed up for information regarding survival, hospitalizations, and ICD therapies since 2010.
Kaplan-Meier survival analysis showed that the rate of appropriate ICD shock therapy at 30-month follow-up was 2.6% among patients who received an ICD for primary prevention compared with 7.4% among those who received a device for secondary prevention (log-rank P < .001). Rates of appropriate ICD shocks among primary prevention patients were 1.1% at 1-year of follow-up and 2.6% at 30 months, whereas the corresponding rates in the secondary prevention group were 3.8% at 1 year and 7.4% at 30 months (log-rank P < .001). A total of 253 patients (4.8%) died during follow-up, 65% of noncardiac causes.
Rates of life-saving appropriate ICD shock therapies among patients implanted with a defibrillator for the primary prevention of SCD in a contemporary real-world setting are lower than reported previously. These findings suggest a need for improved risk stratification and patient selection in this population.
Objectives The present study was designed to explore the 8-year survival benefit of a nonresynchronization implantable cardioverter-defibrillator (ICD) according to a simple risk stratification ...score. Background There is limited information regarding factors that predict the benefit of primary prevention with an ICD during long-term follow-up. Methods This study used a previously developed risk score including 5 clinical factors (New York Heart Association functional class >II, age >70 years, blood urea nitrogen >26 mg/dl, QRS duration >0.12 s, and atrial fibrillation) to evaluate 8-year ICD survival benefit within risk score categories among 1,191 MADIT-II (Multicenter Automatic Defibrillator Implantation Trial II) patients. Results Patients with low (0 risk factors, n = 345) and intermediate risk (1 to 2 risk factors, n = 646) demonstrated a significantly higher probability of survival at 8-year follow-up when treated by ICD as compared with non-ICD therapy (75% vs. 58%, p = 0.004; and 47% vs. 31%, p < 0.001, respectively). By contrast, among high-risk patients (3 or more risk factors, n = 200), there was no significant difference in 8-year survival between the ICD and non-ICD subgroups (19% vs. 17%, p = 0.50). Consistently, multivariate analysis showed that ICD therapy was associated with a significant long-term survival benefit among low- and intermediate-risk patients (hazard ratio HR: 0.52, p < 0.001, and HR: 0.66, p < 0.001, respectively), whereas treatment with an ICD was not associated with a significant benefit among high-risk patients (HR: 0.84, p = 0.25). Conclusions These findings suggest that a simple risk score can identify patients who derive significant long-term benefit from primary ICD therapy. High-risk patients with multiple comorbidities composed 17% of the MADIT-II population and did not derive long-term benefit from nonresynchronization device therapy.
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