Cardiac Resynchronization Defibrillator Therapy for Nonspecific Intraventricular Conduction Delay Versus Right Bundle Branch Block

BackgroundThe benefits of cardiac resynchronization therapy (CRT) in patients with non-left bundle branch block (LBBB) conduction abnormality have not been fully explored.ObjectivesThis study sought to evaluate clinical outcomes among Medicare-aged patients with nonspecific intraventricular conduction delay (NICD) versus right bundle branch block (RBBB) in patients eligible for implantation with a CRT with defibrillator (CRT-D).MethodsUsing the National Cardiovascular Data Registry implantable cardioverter-defibrillator (ICD) registry data between 2010 and 2013, the authors compared outcomes in CRT-eligible patients implanted with CRT-D versus ICD-only therapy among patients with NICD and RBBB. Also, among all CRT-D–implanted patients, the authors compared outcomes in those with NICD versus RBBB. Survival curves and multivariable adjusted hazard ratios (HRs) were used to assess outcomes including hospitalization and death.ResultsIn 11,505 non-LBBB CRT-eligible patients, after multivariable adjustment, among patients with RBBB, CRT-D was not associated with better outcomes, compared with ICD alone, regardless of QRS duration. Among patients with NICD and a QRS ≥150 ms, CRT-D was associated with decreased mortality at 3 years compared with ICD alone (HR: 0.602; 95% confidence interval [CI]: 0.416 to 0.871; p = 0.0071). Among 5,954 CRT-D–implanted patients, after multivariable adjustment NICD compared with RBBB was associated with lower mortality at 3 years in those with a QRS duration of ≥150 ms (HR: 0.757; 95% CI: 0.625 to 0.917; p = 0.0044).ConclusionsAmong non-LBBB CRT-D–eligible patients, CRT-D implantation was associated with better outcomes compared with ICD alone specifically in NICD patients with a QRS duration of ≥150 ms. Careful patient selection should be considered for CRT-D implantation in patients with non-LBBB conduction.     

Fasting Levels of High-Sensitivity Growth Hormone Predict Cardiovascular Morbidity and Mortality : The Malmö Diet and Cancer Study

Background

Both pathological excess and deficiency of growth hormone (GH) are associated with cardiovascular mortality.

Objectives

The goal of this study was to test whether fasting levels of growth hormone measured with a high-sensitivity assay (hs-GH) predict cardiovascular morbidity and mortality at the population level.

Methods

We studied 4,323 participants (age 46 to 68 years; mean age 58 years; 59% women) of the Swedish, population-based Malmö Diet and Cancer study examined in 1991 to 1994. Using multivariate-adjusted Cox proportional hazards models, we related baseline levels of fasting hs-GH to incidence of coronary artery disease, stroke, congestive heart failure, all-cause mortality, and cardiovascular mortality.

Results

During a median follow-up of 16.2 years, hs-GH (hazard ratio [HR]/SD increment of natural logarithm of fasting hs-GH) was independently associated with increased risk of coronary artery disease (397 events; HR: 1.11; 95% confidence interval [CI]: 1.01 to 1.23; p = 0.04), stroke (251 events; HR: 1.18; 95% CI: 1.04 to 1.34; p = 0.01), congestive heart failure (107 events; HR: 1.25; 95% CI: 1.03 to 1.52; p = 0.02), all-cause mortality (645 events; HR: 1.17; 95% CI: 1.08 to 1.26; p < 0.001) and cardiovascular mortality (186 events; HR: 1.43; 95% CI: 1.24 to 1.66; p < 0.001). The addition of hs-GH to a model with conventional cardiovascular risk factors significantly reclassified risk, with a category-free net reclassification improvement (>0) of 0.542 (95% CI: 0.205 to 0.840) in cardiovascular mortality.

Conclusions

Higher values of hs-GH were associated with an increased risk of cardiovascular morbidity and mortality.     

Impact of Aortic Valve Calcification,as Measured by MDCT,on Survival in Patients With Aortic Stenosis : Results of an International Registry Study

Background

Aortic valve calcification (AVC) load measures lesion severity in aortic stenosis (AS) and is useful for diagnostic purposes. Whether AVC predicts survival after diagnosis, independent of clinical and Doppler echocardiographic AS characteristics, has not been studied.

Objectives

This study evaluated the impact of AVC load, absolute and relative to aortic annulus size (AVC_density), on overall mortality in patients with AS under conservative treatment and without regard to treatment.

Methods

In 3 academic centers, we enrolled 794 patients (mean age, 73 ± 12 years; 274 women) diagnosed with AS by Doppler echocardiography who underwent multidetector computed tomography (MDCT) within the same episode of care. Absolute AVC load and AVC_density (ratio of absolute AVC to cross-sectional area of aortic annulus) were measured, and severe AVC was separately defined in men and women.

Results

During follow-up, there were 440 aortic valve implantations (AVIs) and 194 deaths (115 under medical treatment). Univariate analysis showed strong association of absolute AVC and AVC_density with survival (both, p < 0.0001) with a spline curve analysis pattern of threshold and plateau of risk. After adjustment for age, sex, coronary artery disease, diabetes, symptoms, AS severity on hemodynamic assessment, and LV ejection fraction, severe absolute AVC (adjusted hazard ratio [HR]: 1.75; 95% confidence interval [CI]: 1.04 to 2.92; p = 0.03) or severe AVC_density (adjusted HR: 2.44; 95% CI: 1.37 to 4.37; p = 0.002) independently predicted mortality under medical treatment, with additive model predictive value (all, p ≤ 0.04) and a net reclassification index of 12.5% (p = 0.04). Severe absolute AVC (adjusted HR: 1.71; 95% CI: 1.12 to 2.62; p = 0.01) and severe AVC_density (adjusted HR: 2.22; 95% CI: 1.40 to 3.52; p = 0.001) also independently predicted overall mortality, even with adjustment for time-dependent AVI.

Conclusions

This large-scale, multicenter outcomes study of quantitative Doppler echocardiographic and MDCT assessment of AS shows that measuring AVC load provides incremental prognostic value for survival beyond clinical and Doppler echocardiographic assessment. Severe AVC independently predicts excess mortality after AS diagnosis, which is greatly alleviated by AVI. Thus, measurement of AVC by MDCT should be considered for not only diagnostic but also risk-stratification purposes in patients with AS.     

New Electrocardiographic Criteria to Differentiate Acute Pericarditis and Myocardial Infarction

Objective

Transmural myocardial ischemia induces changes in QRS complex and QT interval duration but, theoretically, these changes might not occur in acute pericarditis provided that the injury is not transmural. This study aims to assess whether QRS and QT duration permit distinguishing acute pericarditis and acute transmural myocardial ischemia.

Methods

Clinical records and 12-lead electrocardiogram (ECG) at ×2 magnification were analyzed in 79 patients with acute pericarditis and in 71 with acute ST-segment elevation myocardial infarction (STEMI).

Results

ECG leads with maximal ST-segment elevation showed longer QRS complex and shorter QT interval than leads with isoelectric ST segment in patients with STEMI (QRS: 85.9 ± 13.6 ms vs 81.3 ± 10.4 ms, P = .01; QT: 364.4 ± 38.6 vs 370.9 ± 37.0 ms, P = .04), but not in patients with pericarditis (QRS: 81.5 ± 12.5 ms vs 81.0 ± 7.9 ms, P = .69; QT: 347.9 ± 32.4 vs 347.3 ± 35.1 ms, P = .83). QT interval dispersion among the 12-ECG leads was greater in STEMI than in patients with pericarditis (69.8 ± 20.8 ms vs 50.6 ± 20.2 ms, P <.001). The diagnostic yield of classical ECG criteria (PR deviation and J point level in lead aVR and the number of leads with ST-segment elevation, ST-segment depression, and PR-segment depression) increased significantly (P = .012) when the QRS and QT changes were added to the diagnostic algorithm.

Conclusions

Patients with acute STEMI, but not those with acute pericarditis, show prolongation of QRS complex and shortening of QT interval in ECG leads with ST-segment elevation. These new findings may improve the differential diagnostic yield of the classical ECG criteria.     

Long-term mortality risk in patients with an implantable cardioverter–defibrillator: Influence of heart rate and QRS duration

Background

A paucity of studies has investigated the role of autonomic cardiac regulation as well as cardiac conduction in relation to prognosis in implantable cardioverter–defibrillator (ICD) patients. Therefore, we examined the association of heart rate and QRS duration with long-term mortality risk in first-time ICD patients, adjusting also for measures of emotional distress.

Methods

Resting heart rate and QRS duration were assessed prior to ICD implantation in 448 patients. Primary study endpoint was all-cause mortality (up to 6.0 year follow-up, median follow-up of 5.6 years (IQR: 1.9)). The impact of heart rate and QRS duration on time to all-cause mortality was separately assessed with Cox proportional hazard regression analysis, adjusting for clinical factors and symptoms of depression and anxiety.

Results

Mean (SD) heart rate was 68.0 ± 13.3 bpm and mean QRS duration was 130.9 ± 36.9 ms. Heart rate of ≥ 80 bpm was associated with increased risk of mortality (HR = 1.86; 95% CI = 1.15–3.00; p = .011) in unadjusted analysis. In adjusted analyses, this relationship remained significant both with depression (HR = 1.86, 95% CI = 1.12–3.09; p = .017) and anxiety (HR = 1.82, 95% CI = 1.10–3.03; p = .021) and clinical measures as covariates. QRS duration of ≥ 120 ms was associated with impaired prognosis in unadjusted analysis (HR = 2.00, 95% CI = 1.27–3.14; p = .003), but was reduced to non-significance in adjusted analysis when medical comorbidities were included (HR = 1.15, 95% CI = 0.70–1.89; p = .60).

Conclusions

This study shows that increased heart rate is associated with impaired prognosis. Since heart rate is a relatively easy measurable parameter of autonomic functioning, heart rate should be included as a measure for risk stratification in daily clinical practice.     

Impaired Recovery of Left Ventricular Function in Patients With Cardiomyopathy and Left Bundle Branch Block

Background

Patients with left bundle branch block (LBBB) often respond to cardiac resynchronization therapy (CRT) with left ventricular ejection fraction (LVEF) improvement. Guideline-directed medical therapy (GDMT), not CRT, is first-line therapy for patients with reduced LVEF with LBBB. However, there are little data on how patients with reduced LVEF and LBBB respond to GDMT.

Prognostic Value of Elevated Levels of Intestinal Microbe-Generated Metabolite Trimethylamine-N-Oxide in Patients With Heart Failure : Refining the Gut Hypothesis

Background

Altered intestinal function is prevalent in patients with heart failure (HF), but its role in adverse outcomes is unclear.

Objectives

This study investigated the potential pathophysiological contributions of intestinal microbiota in HF.

Methods

We examined the relationship between fasting plasma trimethylamine-N-oxide (TMAO) and all-cause mortality over a 5-year follow-up in 720 patients with stable HF.

Results

The median TMAO level was 5.0 μM, which was higher than in subjects without HF (3.5 μM; p < 0.001). There was modest but significant correlation between TMAO concentrations and B-type natriuretic peptide (BNP) levels (r = 0.23; p < 0.001). Higher plasma TMAO levels were associated with a 3.4-fold increased mortality risk. Following adjustments for traditional risk factors and BNP levels, elevated TMAO levels remained predictive of 5-year mortality risk (hazard ratio [HR]: 2.2; 95% CI: 1.42 to 3.43; p < 0.001), as well as following the addition of estimated glomerular filtration rate to the model (HR: 1.75; 95% CI: 1.07 to 2.86; p < 0.001).

Conclusions

High TMAO levels were observed in patients with HF, and elevated TMAO levels portended higher long-term mortality risk independent of traditional risk factors and cardiorenal indexes.     

Pro-Substance P for Evaluation of Risk in Acute Myocardial Infarction

Background

Pro-substance P (ProSP) is a stable surrogate marker for labile substance P, which has pro-inflammatory effects, increases platelet aggregation and clot strength, and reduces fibrinolysis.

Objectives

This study assessed whether ProSP was associated with poor prognosis after acute myocardial infarction (AMI) to identify novel pathophysiological mechanisms.

Methods

ProSP was measured in 1,148 AMI patients (825 men, mean age 66.2 ± 12.8 years). Endpoints were major adverse cardiac events (composite of death, reinfarction, and heart failure [HF] hospitalization), death/reinfarction, and death/HF. GRACE (Global Registry of Acute Coronary Events) scores were compared with ProSP for death and/or reinfarction at 6 months.

Results

During 2-year follow-up, there were 140 deaths, 112 HF hospitalizations, and 149 re-AMI. ProSP levels were highest on the first 2 days after admission and related to estimated glomerular filtration rate, age, history of diabetes, ischemic heart disease or hypertension, Killip class, left ventricular wall motion index, and sex. Multivariate Cox regression models showed ProSP level was a predictor of major adverse events (hazard ratio [HR]: 1.30; 95% confidence interval [CI]: 1.10 to 1.54; p < 0.002), death and/or AMI (HR: 1.42; 95% CI: 1.20 to 1.68; p < 0.0005), death and/or HF (HR: 1.38; 95% CI: 1.14 to 1.67; p < 0.001). ProSP levels with GRACE scores were independent predictors of 6-month death and/or reinfarction (p < 0.0005 for both). ProSP-adjusted GRACE scores reclassified patients significantly (overall category-free net reclassification improvement of 31.6 (95% CI: 14.3 to 49.0; p < 0.0005) mainly by down-classifying those without endpoints.

Conclusions

ProSP levels post-AMI are prognostic for death, recurrent AMI, or HF, and they improve risk prediction of GRACE scores, predominantly by down-classifying risk in those without events.     

Prognostic implications of quantitative evaluation of baseline Q-wave width in ST-segment elevation myocardial infarction

Objectives

To evaluate quantitative relationships between baseline Q-wave width and 90-day outcomes in ST-segment elevation myocardial infarction (STEMI).

Background

Baseline Q-waves are useful in predicting clinical outcomes after MI.

Methods

3589 STEMI patients were assessed from a multi-centre study.

Results

1156 patients of the overall cohort had pathologic Q-waves. The 90-day mortality and the composite of mortality, congestive heart failure (CHF), or cardiogenic shock (p < 0.001 for both outcomes) rose as Q-wave width increased. After adapting a threshold ≥ 40 ms for inferior and ≥ 20 ms for lateral/apical MI in all patients (n = 3065) with any measureable Q-wave we found hazard ratios (HR) for mortality (HR: 2.44, 95% confidence interval (CI) (1.54–3.85), p < 0.001) and the composite (HR: 2.32, 95% CI (1.70–3.16), p < 0.001). This improved reclassification of patients experiencing the composite endpoint versus the conventional definition (net reclassification index (NRI): 0.23, 95% CI (0.09-0.36), p < 0.001) and universal MI definition (NRI: 0.15, 95% CI (0.02–0.29), p = 0.027).

Conclusions

The width of the baseline Q-wave in STEMI adds prognostic value in predicting 90-day clinical outcomes. A threshold of ≥ 40 ms in inferior and ≥ 20 ms for lateral/apical MI enhances prognostic insight beyond current criteria.     

Clinical Effectiveness of CRT and ICD Therapy in Heart Failure Patients by Racial/Ethnic Classification : Insights From the IMPROVE HF Registry

Background

Clinical trials have demonstrated benefit for cardiac resynchronization therapy (CRT) and implantable cardioverter-defibrillator (ICD) therapies in patients with heart failure with reduced ejection fraction (HFrEF); yet, questions have been raised with regard to the benefit of device therapy for minorities.

Objectives

The purpose of this study was to determine the clinical effectiveness of CRT and ICD therapies as a function of race/ethnicity in outpatients with HFrEF (ejection fraction ≤35%).

Methods

Data from IMPROVE HF (Registry to Improve the Use of Evidence-Based Heart Failure Therapies in the Outpatient Setting) were analyzed by device status and race/ethnicity among guideline-eligible patients for mortality at 24 months. Multivariate Generalized Estimating Equations analyses were conducted, adjusting for patient and practice characteristics.

Results

The ICD/cardiac resynchronization defibrillator (CRT-D)–eligible cohort (n = 7,748) included 3,391 (44%) non-Hispanic white, 719 (9%) non-Hispanic black, and 3,638 (47%) other racial/ethnic minorities or race-not-documented patients. The cardiac resynchronization pacemaker (CRT-P)/CRT-D–eligible cohort (n = 1,188) included 596 (50%) non-Hispanic white, 99 (8%) non-Hispanic black, and 493 (41%) other/not-documented patients. There was clinical benefit associated with ICD/CRT-D therapy (adjusted odds ratio: 0.64, 95% confidence interval: 0.52 to 0.79, p = 0.0002 for 24-month mortality), which was of similar proportion in white, black, and other minority/not-documented patients (device–race/ethnicity interaction p = 0.7861). For CRT-P/CRT-D therapy, there were also associated mortality benefits (adjusted odds ratio: 0.55, 95% confidence interval: 0.33 to 0.91, p = 0.0222), and the device–race/ethnicity interaction was not significant (p = 0.5413).

Conclusions

The use of guideline-directed CRT and ICD therapy was associated with reduced 24-month mortality without significant interaction by racial/ethnic group. Device therapies should be offered to eligible heart failure patients, without modification based on race/ethnicity.     

Increased Mortality Associated With Digoxin in Contemporary Patients With Atrial Fibrillation : Findings From the TREAT-AF Study

Background

Despite endorsement of digoxin in clinical practice guidelines, there exist limited data on its safety in atrial fibrillation/flutter (AF).

Objectives

The goal of this study was to evaluate the association of digoxin with mortality in AF.

Methods

Using complete data of the TREAT-AF (The Retrospective Evaluation and Assessment of Therapies in AF) study from the U.S. Department of Veterans Affairs (VA) healthcare system, we identified patients with newly diagnosed, nonvalvular AF seen within 90 days in an outpatient setting between VA fiscal years 2004 and 2008. We used multivariate and propensity-matched Cox proportional hazards to evaluate the association of digoxin use with death. Residual confounding was assessed by sensitivity analysis.

Results

Of 122,465 patients with 353,168 person-years of follow-up (age 72.1 ± 10.3 years, 98.4% male), 28,679 (23.4%) patients received digoxin. Cumulative mortality rates were higher for digoxin-treated patients than for untreated patients (95 vs. 67 per 1,000 person-years; p < 0.001). Digoxin use was independently associated with mortality after multivariate adjustment (hazard ratio [HR]: 1.26, 95% confidence interval [CI]: 1.23 to 1.29, p < 0.001) and propensity matching (HR: 1.21, 95% CI: 1.17 to 1.25, p < 0.001), even after adjustment for drug adherence. The risk of death was not modified by age, sex, heart failure, kidney function, or concomitant use of beta-blockers, amiodarone, or warfarin.

Conclusions

Digoxin was associated with increased risk of death in patients with newly diagnosed AF, independent of drug adherence, kidney function, cardiovascular comorbidities, and concomitant therapies. These findings challenge current cardiovascular society recommendations on use of digoxin in AF.     

Management Practices and Major Infections After Cardiac Surgery

Background

Infections are the most common noncardiac complication after cardiac surgery, but their incidence across a broad range of operations, as well as the management factors that shape infection risk, remain unknown.

Objectives

This study sought to prospectively examine the frequency of post-operative infections and associated mortality, and modifiable management practices predictive of infections within 65 days from cardiac surgery.

Methods

This study enrolled 5,158 patients and analyzed independently adjudicated infections using a competing risk model (with death as the competing event).

Results

Nearly 5% of patients experienced major infections. Baseline characteristics associated with increased infection risk included chronic lung disease (hazard ratio [HR]: 1.66; 95% confidence interval [CI]: 1.21 to 2.26), heart failure (HR: 1.47; 95% CI: 1.11 to 1.95), and longer surgery (HR: 1.31; 95% CI: 1.21 to 1.41). Practices associated with reduced infection risk included prophylaxis with second-generation cephalosporins (HR: 0.70; 95% CI: 0.52 to 0.94), whereas post-operative antibiotic duration >48 h (HR: 1.92; 95% CI: 1.28 to 2.88), stress hyperglycemia (HR: 1.32; 95% CI: 1.01 to 1.73); intubation time of 24 to 48 h (HR: 1.49; 95% CI: 1.04 to 2.14); and ventilation >48 h (HR: 2.45; 95% CI: 1.66 to 3.63) were associated with increased risk. HRs for infection were similar with either <24 h or <48 h of antibiotic prophylaxis. There was a significant but differential effect of transfusion by surgery type (excluding left ventricular assist device procedures/transplant) (HR: 1.13; 95% CI: 1.07 to 1.20). Major infections substantially increased mortality (HR: 10.02; 95% CI: 6.12 to 16.39).

Conclusions

Major infections dramatically affect survival and readmissions. Second-generation cephalosporins were strongly associated with reduced major infection risk, but optimal duration of antibiotic prophylaxis requires further study. Given practice variations, considerable opportunities exist for improving outcomes and preventing readmissions. (Management Practices and Risk of Infection Following Cardiac Surgery; NCT01089712)     

Extent of Coronary and Myocardial Disease and Benefit From Surgical Revascularization in LV Dysfunction

Background

Patients with ischemic left ventricular dysfunction have higher operative risk with coronary artery bypass graft surgery (CABG). However, those whose early risk is surpassed by subsequent survival benefit have not been identified.

Objectives

This study sought to examine the impact of anatomic variables associated with poor prognosis on the effect of CABG in ischemic cardiomyopathy.

Methods

All 1,212 patients in the STICH (Surgical Treatment of IsChemic Heart failure) surgical revascularization trial were included. Patients had coronary artery disease (CAD) and ejection fraction (EF) of ≤35% and were randomized to receive CABG plus medical therapy or optimal medical therapy (OMT) alone. This study focused on 3 prognostic factors: presence of 3-vessel CAD, EF below the median (27%), and end-systolic volume index (ESVI) above the median (79 ml/m²). Patients were categorized as having 0 to 1 or 2 to 3 of these factors.

Results

Patients with 2 to 3 prognostic factors (n = 636) had reduced mortality with CABG compared with those who received OMT (hazard ratio [HR]: 0.71; 95% confidence interval [CI]: 0.56 to 0.89; p = 0.004); CABG had no such effect in patients with 0 to 1 factor (HR: 1.08; 95% CI: 0.81 to 1.44; p = 0.591). There was a significant interaction between the number of factors and the effect of CABG on mortality (p = 0.022). Although 30-day risk with CABG was higher, a net beneficial effect of CABG relative to OMT was observed at >2 years in patients with 2 to 3 factors (HR: 0.53; 95% CI: 0.37 to 0.75; p<0.001) but not in those with 0 to 1 factor (HR: 0.88; 95% CI: 0.59 to 1.31; p = 0.535).

Conclusions

Patients with more advanced ischemic cardiomyopathy receive greater benefit from CABG. This supports the indication for surgical revascularization in patients with more extensive CAD and worse myocardial dysfunction and remodeling. (Comparison of Surgical and Medical Treatment for Congestive Heart Failure and Coronary Artery Disease [STICH]; NCT00023595)     

Prognostic value of fragmented QRS in cardiac AL amyloidosis

Background

In light-chain (AL) cardiac amyloidosis, the 12-lead electrocardiogram (ECG) reflects myocardial amyloid infiltration with low limb voltages, pseudoinfarction patterns, and conduction abnormalities. Moreover, it is not unusual to see “aspecific” QRS complex abnormalities, such as notches and RsR′ pattern in the absence of QRS prolongation, i.e. a fragmentation of QRS complexes (fQRS), that has been associated with myocardial scars and prognosis. Since cardiomyocyte damage and interstitial fibrosis are associated with cardiac amyloid deposition, aim of the present study was to analyze the prevalence and the potential prognostic value of fQRS in patients with cardiac amyloidosis.

Methods

We enrolled 375 consecutive untreated patients in whom a first AL amyloidosis diagnosis was concluded between 2008 and 2010, 264 with and 111 without heart involvement. Patients with a positive history of coronary disease were excluded from the analysis.

Results

The prevalence of fQRS was significantly higher in patients with cardiac AL amyloidosis (28.5% vs. 11.7%; p = 0.0008). After a median follow-up of 561 days, Kaplan–Meier survival analysis revealed a significantly higher mortality in the fQRS group when compared with the “normal” QRS group (p = 0.0008). No association was found between the presence of fQRS and the duration of PQ, QRS, and QTc intervals, the presence of peripheral low voltages or pseudonecrosis, NT-proBNP serum levels or cardiac wall thickness.

Conclusions

In patients with cardiac AL amyloidosis, the presence of fQRS at diagnosis has an independent prognostic value. Such a simple and cheap analysis in patients' diagnostic work-up may improve diagnosis and prognostic stratification.     

QRS analysis using wavelet transformation for the prediction of response to cardiac resynchronization therapy: A prospective pilot study

Background

Wider QRS and left bundle branch block morphology are related to response to cardiac resynchronization therapy (CRT). A novel time-frequency analysis of the QRS complex may provide additional information in predicting response to CRT.

Methods

Signal-averaged electrocardiograms were prospectively recorded, before CRT, in orthogonal leads and QRS decomposition in three frequency bands was performed using the Morlet wavelet transformation.

Results

Thirty eight patients (age 65 ± 10 years, 31 males) were studied. CRT responders (n = 28) had wider baseline QRS compared to non-responders and lower QRS energies in all frequency bands. The combination of QRS duration and mean energy in the high frequency band had the best predicting ability (AUC 0.833, 95%CI 0.705-0.962, p = 0.002) followed by the maximum energy in the high frequency band (AUC 0.811, 95%CI 0.663-0.960, p = 0.004).

Conclusions

Wavelet transformation of the QRS complex is useful in predicting response to CRT.     

The prognostic significance of fragmented QRS in patients with left ventricular noncompaction cardiomyopathy

Background

Fragmented QRS complexes (fQRS) were proven to be associated with the prognosis of several heart diseases. However, no data is available regarding fQRS in left ventricular noncompaction cardiomyopathy (LVNC), in which the outcome varies greatly and a simple yet practicable prognostic predictor is needed. The purpose of this study was to determine the prognostic value of fQRS in LVNC patients.

Methods

Sixty-four LVNC patients were evaluated. Fragmented narrow QRS (f-nQRS) included single or multiple notches in the R or S wave in at least 2 contiguous electrocardiogram (ECG) leads and QRS duration < 120 ms, fragmented wide QRS (f-wQRS) included more than 2 notches and QRS duration > 120 ms.

Results

f-nQRS and f-wQRS was present in 24 (38%) and 7 (11%) patients respectively. During follow-up, 13 patients died and 7 patients underwent heart transplantation. Kaplan-Meier analysis revealed that compared with the non–f-nQRS group, the f-nQRS group associated with a significantly lower survival (P = 0.005). The f-wQRS group also demonstrated a substantially lower survival as compared with the non–f-wQRS group (P = 0.02). Multivariate analysis indicated f-nQRS was an independent predictor of all-cause mortality (HR: 5.33; P = 0.045).

Conclusions

In LVNC patients, the presence of f-nQRS has significant prognostic value and may provide a valid method of risk stratification.     

Gender-related differences of diabetic patients undergoing percutaneous coronary intervention with drug-eluting stents: A real-life multicenter experience

Background

Gender-based differences in diabetic patients are understudied in the field of percutaneous coronary intervention (PCI) with drug-eluting stents.

Methods

Data were obtained from a multicenter registry of 2420 consecutive patients with diabetes mellitus (DM) who underwent PCI with paclitaxel- or sirolimus-eluting stents between 2003 and 2009. Among them, 679 (28.1%) women were compared to 1741 (71.9%) men in terms of clinical aspects and major adverse cardiac events (MACE), including all-cause death, myocardial infarction (MI) and target lesion revascularization (TLR). Target vessel revascularization (TVR) and any revascularization were also reported.

Results

Women were less numerous, older, used more insulin and showed more tortuous coronary arteries, while men were more frequently smokers and received larger stents. At the median follow-up of 24.3 months (interquartile range 12.3–39.7), MACE, TVR and any revascularization did not significantly differ between females and males (19.9% vs 18.7%, 12.2% vs 13.4%, 14.1% vs 15.1%, respectively). At multivariable analysis of the overall cohort, female gender was not a predictor of MACE (hazard ratio [HR] 1.02, 95% confidence interval [CI] 0.92–2.36, p = 0.11), death (HR 1.04, 95% CI 0.84–1.24, p = 0.86), MI (HR 1.48, 95% CI 0.92–2.36, p = 0.11), and TLR (HR 1.14, 95% CI 0.85–1.52, p = 0.38).

Conclusion

In this registry of diabetic patients treated by drug-eluting stents, women were less represented, older and needed more insulin compared to men who, on the other hand, received larger stents. Gender-related outcomes were similar and female sex did not predict MACE.     

Prognostic significance of the absence of normal septal Q waves before aortic valve replacement

Purpose

Aim of this study was to investigate the prognostic significance of absence of septal Q waves in patients scheduled for aortic valve replacement.

Material and Methods

Sixty-one patients who underwent isolated aortic valve replacement for aortic stenosis were retrospectively evaluated. Septal Q waves were defined as Q waves of < 2 mm in amplitude and < 40 ms in width and absence of septal Q waves was defined as simultaneous loss of Q waves from at least three of the leads I, aVL, V5 and V6. Septal Q waves were absent in 17 patients (Group AQ, 27.8%) and were present in 44 patients (Group PQ, 72.1 %) preoperatively. Newly developed AV block > 1st degree and newly developed left bundle branch block were primary endpoints.

Results

Preoperatively, absence of normal septal Q waves was significantly associated with increased risk of postoperative AV block (HR: 11.18, range 1.37–91.21, 95% CI, p = 0.02) whereas it was not associated with increased risk for newly developed LBBB (HR: 3.15 0.62–15.83, 95% CI, p = 0.16).

Conclusion

Absence of normal septal Q waves in the preoperative ECG may predict further delay in conduction which might develop in the early postoperative course of aortic valve replacement.     

Prognostic Significance of LGE by CMR in Aortic Stenosis Patients Undergoing Valve Replacement

Background

Prior studies have shown that late gadolinium enhancement (LGE) by cardiac magnetic resonance (CMR) can detect focal fibrosis in aortic stenosis (AS), suggesting that it might predict higher mortality risk.

Objectives

This study was conducted to evaluate whether LGE-CMR can predict post-operative survival in patients with severe AS undergoing aortic valve replacement (AVR).

Methods

We prospectively evaluated survival (all-cause and cardiovascular disease related) according to LGE-CMR status in 154 consecutive AS patients (96 men; mean age: 74 ± 6 years) without a history of myocardial infarction undergoing surgical AVR and in 40 AS patients undergoing transcatheter aortic valve replacement (TAVR).

Results

LGE was present in 29% of patients undergoing surgical AVR and in 50% undergoing TAVR. During a median follow-up of 2.9 years, 21 patients undergoing surgical AVR and 20 undergoing TAVR died. In surgical AVR, the presence of LGE predicted higher post-operative mortality (odds ratio: 10.9; 95% confidence interval [CI]: 1.2 to 100.0; p = 0.02) and worse all-cause survival (73% vs. 88%; p = 0.02 by log-rank test) and cardiovascular disease related survival (85% vs. 95%; p = 0.03 by log-rank test) on 5-year Kaplan-Meier estimates of survival after surgical AVR. Multivariate Cox analysis identified the presence of LGE (hazard ratio: 2.8; 95% CI: 1.3 to 6.9; p = 0.025) and New York Heart Association functional class III/IV (hazard ratio: 3.2; 95% CI: 1.1 to 8.1; p < 0.01) as the sole independent predictors of all-cause mortality after surgical AVR. The presence of LGE also predicted higher all-cause mortality (p = 0.05) and cardiovascular disease related mortality (p = 0.03) in the subgroup of patients without angiographic coronary artery disease (n = 110) and higher cardiovascular disease related mortality in 25 patients undergoing transfemoral TAVR.

Conclusions

The presence of LGE indicating focal fibrosis or unrecognized infarct by CMR is an independent predictor of mortality in patients with AS undergoing AVR and could provide additional information in the pre-operative evaluation of risk in these patients.     

Stent Thrombosis in New-Generation Drug-Eluting Stents in Patients With STEMI Undergoing Primary PCI : A Report From SCAAR

Background

Some concerns still have not been resolved about the long-term safety of drug-eluting stents (DES) in patients with acute STEMI.

Objectives

The aim of this study was to evaluate the stent thrombosis (ST) rate up to 3 years in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention (PCI) with new-generation drug-eluting stents (n-DES) compared with bare-metal stents (BMS) and old-generation drug-eluting stents (o-DES) enrolled in the SCAAR (Swedish Coronary Angiography and Angioplasty Registry).

Methods

From January 2007 to January 2013, 34,147 patients with STEMI were treated by PCI with n-DES (n = 4,811), o-DES (n = 4,271), or BMS (n = 25,065). The risks of early/late (up to 1 year) and very late definite ST (after 1 year) were estimated.

Results

Cox regression landmark analysis showed a significantly lower risk of early/late ST in patients treated with n-DES (hazard ratio [HR]: 0.65; 95% confidence interval [CI]: 0.43 to 0.99; p = 0.04) and o-DES (HR: 0.60; 95% CI: 0.41 to 0.89; p = 0.01) compared with the BMS group. The risk of very late ST was similar between the n-DES and BMS groups (HR: 1.52; 95% CI: 0.78 to 2.98; p = 0.21), whereas a higher risk of very late ST was observed with o-DES compared with BMS (HR: 2.88; 95% CI: 1.70 to 4.89; p < 0.01).

Conclusions

Patients treated with n-DES have a lower risk of early/late ST than patients treated with BMS. The risk of very late ST is low and comparable between n-DES and BMS up to 3 years of follow-up, whereas o-DES treatment is associated with an increased risk of very late ST. The current STEMI guidelines might require an update in light of the results of this and other recent studies.