Effect of Implantable Cardioverter-defibrillators in Nonischemic Heart Failure According to Background Medical Therapy: Extended Follow-up of the DANISH Trial.

BACKGROUND: The Heart Failure Collaboratory (HFC) score integrates types and dosages of guideline-directed pharmacotherapies for heart failure (HF) with reduced ejection fraction (HFrEF). We examined the effects of cardioverter-defibrillator (ICD) implantation according to the modified HFC (mHFC) score in 1116 patients with nonischemic HFrEF from the Danish Study to Assess the Efficacy of ICDs in Patients with Nonischemic Systolic HF on Mortality (DANISH). METHODS AND RESULTS: Patients were assigned scores for renin-angiotensin-system inhibitors, beta-blockers and mineralocorticoid receptor antagonists (0, no use; 1, < 50% of maximum dosage; 2, ≥ 50% of maximum dosage). The maximum score was 6, corresponding to ≥ 50% of maximum dosage for all therapies. The median baseline mHFC score was 4, and the median follow-up was 9.5 years. Compared with an mHFC score of 3-4, an mHFC score of 1-2 was associated with a higher rate of all-cause death (mHFC = 1-2: adjusted HR 1.67 [95% CI, 1.23-2.28]; mHFC = 3-4, reference; mHFC = 5-6: adjusted HR 1.07 [95% CI, 0.87-1.31]). ICD implantation did not reduce all-cause death compared with control (reference) (HR 0.89 [95% CI, 0.74-1.08]), regardless of mHFC score (mHFC = 1-2: HR 0.98 [95% CI, 0.56-1.71]; mHFC = 3-4: HR 0.89 [95% CI,0.66-1.20]; mHFC = 5-6: HR 0.85 [95% CI, 0.64-1.12]; Pinteraction, 0.65). Similarly, ICD implantation did not reduce cardiovascular death (HR 0.87 [95% CI, 0.70-1.09]), regardless of mHFC score (Pinteraction, 0.59). The ICD group had a lower rate of sudden cardiovascular death (HR, 0.60 [95% CI,0.40-0.92]); this association was not modified by mHFC score (Pinteraction, 0.35). CONCLUSIONS: Lower mHFC scores were associated with higher rates of all-cause death. ICD implantation did not result in an overall survival benefit in patients with nonischemic HFrEF, regardless of mHFC score.

New York Heart Association functional class and implantable cardioverter-defibrillator in non-ischaemic heart failure with reduced ejection fraction: Extended follow-up of the DANISH trial.

AIMS: Current guidelines recommend implantable cardioverter-defibrillator (ICD) therapy in patients with heart failure, a left ventricular ejection fraction of ≤35%, and New York Heart Association (NYHA) class II-III. However, the evidence regarding the benefit of primary prevention ICD is less consistent in patients with NYHA class III. We investigated the long-term effects of primary prevention ICD implantation according to NYHA class in an extended follow-up study of the DANISH trial. METHODS AND RESULTS: The DANISH trial randomized 1116 patients with non-ischaemic heart failure with reduced ejection fraction (HFrEF) to ICD implantation or usual care. Outcomes were analysed according to NYHA class at baseline (NYHA class II and III/IV). The primary outcome was all-cause mortality. Of the 1116 patients randomized in the DANISH trial, 597 (53.5%) were in NYHA class II at baseline, 505 (45.3%) in NYHA class III, and 14 (1.3%) in NYHA class IV. During a median follow-up of 9.5 years, NYHA class III/IV, compared with NYHA class II, were associated with a greater long-term rate of all-cause mortality (hazard ratio [HR] 1.52, 95% confidence interval [CI] 1.20-1.93) and cardiovascular death (HR 1.95 [1.47-2.60]). ICD implantation, compared with usual care, did not reduce the long-term rate of all-cause mortality (all participants: HR 0.89 [95% CI 0.74-1.08]; NYHA class II: HR 0.85 [0.64-1.13]; NYHA class III/IV: HR 0.89 [0.69-1.14]; pinteraction = 0.78) or cardiovascular death (all participants: HR 0.87 [95% CI 0.70-1.09]; NYHA class II: HR 0.78 [0.54-1.12]; NYHA class III/IV: HR 0.89 [0.67-1.19]; pinteraction = 0.58), irrespective of NYHA class. Similarly, NYHA class did not modify the beneficial effects of ICD implantation on sudden cardiovascular death (all participants: HR 0.60 [95% CI 0.40-0.92]; NYHA class II: HR 0.73 [0.40-1.36]; NYHA class III/IV: HR 0.52 [0.29-0.94]; pinteraction = 0.39). CONCLUSIONS: In patients with non-ischaemic HFrEF, ICD implantation, compared with usual care, did not reduce the overall mortality rate, but it did reduce sudden cardiovascular death, regardless of baseline NYHA class. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT00542945.

Association between QRS shortening and mortality after cardiac resynchronization therapy: Results from the DANISH study.

BACKGROUND: Changes in QRS duration (∆QRS) are often used in the clinical setting to evaluate the effect of cardiac resynchronization therapy (CRT), although an association between ∆QRS and outcomes is not firmly established. We aimed to assess the association between mortality and ∆QRS after CRT in patients from the DANISH (Danish Study to Assess the Efficacy of ICDs in Patients with Non-Ischemic Systolic Heart Failure on Mortality) study. METHODS: We included all patients from DANISH who received a CRT device and had available QRS duration data before and after implantation. Cox proportional hazards models were used to assess associations between ∆QRS (post-CRT QRS minus pre-CRT QRS) and mortality. RESULTS: Complete data were available in 572 patients. Median baseline QRS duration was 160 ms (IQR [146;180]). Post-CRT QRS was recorded a median of 48 days (IQR [33;86]) after implantation, and the median ∆QRS was -14 ms (IQR [-38;-3]). During a median follow-up of 4.1 years (IQR [2.5;5.8]), 106 patients died. In crude Cox regression, all-cause mortality was reduced by 6% per 10 ms shortening of QRS (HR 0.94; CI: 0.88-1.00, p = 0.04). The effect did not remain significant after multivariable adjustment (HR 1.01, CI: 0.93-1.10, p = 0.77). Further, no association was found between ∆QRS and improvement of New York Heart Association functional class at 6 months (OR 1.03, CI: 0.96-1.10, p = 0.42). CONCLUSION: In a large cohort of patients with non-ischemic cardiomyopathy, reduction of QRS duration after CRT was not associated with changes in mortality during long-term follow-up.

Estimated Glomerular Filtration Rate and Implantable Cardioverter-Defibrillator in Nonischemic Systolic Heart Failure: Extended Follow-Up of DANISH.

BACKGROUND: Patients with heart failure and chronic kidney disease (CKD) may have an increased risk of death from causes competing with arrhythmic death, which could have implications for the efficacy of implantable cardioverter-defibrillators (ICDs). We examined the long-term effects of primary prophylactic ICD implantation, compared with usual care, according to baseline CKD status in an extended follow-up study of DANISH (Danish Study to Assess the Efficacy of ICDs in Patients With Nonischemic Systolic Heart Failure on Mortality). METHODS AND RESULTS: In the DANISH trial, 1116 patients with nonischemic heart failure with reduced ejection fraction were randomized to receive an ICD (N=556) or usual care (N=550). Outcomes were analyzed according to CKD status (estimated glomerular filtration rate ≥/<60 mL/min per 1.73 m2) at baseline. In total, 1113 patients had an available estimated glomerular filtration rate measurement at baseline (median estimated glomerular filtration rate 73 mL/min per 1.73 m2), and 316 (28%) had CKD. During a median follow-up of 9.5 years, ICD implantation, compared with usual care, did not reduce the rate of all-cause mortality (no CKD, HR, 0.82 [95% CI, 0.64-1.04]; CKD, HR, 1.02 [95% CI, 0.75-1.38]; Pinteraction=0.31) or cardiovascular death (no CKD, HR, 0.77 [95% CI, 0.58-1.03]; CKD, HR, 1.05 [95% CI, 0.73-1.51]; Pinteraction=0.20), irrespective of baseline CKD status. Similarly, baseline CKD status did not modify the beneficial effects of ICD implantation on sudden cardiovascular death (no CKD, HR, 0.57 [95% CI, 0.32-1.00]; CKD, HR, 0.65 [95% CI, 0.34-1.24]; Pinteraction=0.70). CONCLUSIONS: ICD implantation, compared with usual care, did not reduce the overall mortality rate, but it did reduce the rate of sudden cardiovascular death, regardless of baseline kidney function in patients with nonischemic heart failure with reduced ejection fraction. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00542945.

Interplay between natriuretic peptides and left atrial mechanics and the relation to recurrence of atrial fibrillation following catheter ablation.

The relationship between natriuretic peptides and atrial distension is not fully understood. We sought to examine their interrelationship and how they relate to atrial fibrillation (AF) recurrence following catheter ablation. We analyzed patients enrolled in the AMIO-CAT trial (amiodarone vs. placebo for reducing AF recurrence). Echocardiography and natriuretic peptides were assessed at baseline. Natriuretic peptides included mid-regional proANP (MR-proANP) and N-terminal proBNP (NT-proBNP). Atrial distension was assessed by left atrial strain measured by echocardiography. The endpoint was AF recurrence within 6 months after a 3-month blanking period. Logistic regression was used to assess the association between log-transformed natriuretic peptides and AF. Multivariable adjustments were made for age, gender, randomization, and left ventricular ejection fraction. Of 99 patients, 44 developed AF recurrence. No differences in natriuretic peptides nor echocardiography were observed between the outcome groups. In unadjusted analyses, neither MR-proANP nor NT-proBNP were significantly associated with AF recurrence [MR-proANP: OR = 1.06 (0.99-1.14), per 10% increase; NT-proBNP: OR = 1.01 (0.98-1.05), per 10% increase]. These findings were consistent after multivariable adjustments. However, atrial strain significantly modified the association between MR-proANP and AF (p for interaction = 0.009) such that MR-proANP was associated with AF in patients with high atrial strain [OR = 1.24 (1.06-1.46), p = 0.008, per 10% increase] but not in patients with low atrial strain. In patients with high atrial strain, an MR-proANP > 116 pmol/L posed a fivefold higher risk of AF recurrence [HR = 5.38 (2.19-13.22)]. Atrial natriuretic peptide predicts AF recurrence in patients with preserved atrial distension. Assessing atrial strain may assist the interpretation of natriuretic peptides.

Reduced inferior wall longitudinal strain is associated with malignant arrhythmias in non-ischemic heart failure.

BACKGROUND: Reduced systolic myocardial function in the inferior region of the left ventricle has been suggested to be associated with malignant arrhythmias. We tested this hypothesis in patients with non-ischemic heart failure. METHODS: Patients with non-ischemic heart failure (left ventricular ejection fraction [LVEF] < 35%) were evaluated by 2D-speckle-tracking echocardiography. The regional longitudinal strain was calculated for each of the six left ventricular walls. The reduced regional function was defined as strain below the median. The outcome was a composite of sudden cardiac death, admission with sustained ventricular arrhythmia, resuscitated cardiac arrest, and appropriate therapy from a primary prophylactic implantable cardioverter defibrillator. Time-to-first-event analysis was performed using a Cox model. RESULTS: From two centers, 401 patients were included (median age: 63 years, 72% male) with a median LVEF of 25% (interquartile range [IQR] 20;30), and a median inferior wall strain of -9.0% (-12.5; -5.4). During a median follow-up of 4.0 years, 52 outcomes occurred. After multivariate adjustment for clinical and electrocardiographic parameters, inferior wall strain was independently associated with the outcome (HR 2.50 [1.35; 4.62], p = .003). No independent association was found between the composite outcome and reduced strain in any of the other left ventricular walls, Global Longitudinal Strain (HR 1.66 [0.93; 2.98], p = .09), or LVEF (HR 1.33 [0.75; 2.33], p = .33). CONCLUSIONS: Below median strain in the left ventricular inferior region was independently associated with a 2.5-fold increase in the risk of malignant arrhythmias and sudden cardiac death in patients with non-ischemic heart failure.

Comparison of Investigator-Reported and Centrally Adjudicated Heart Failure Outcomes in the EMPEROR-Reduced Trial.

BACKGROUND: There is limited published information on outcome adjudication in heart failure (HF). OBJECTIVES: The authors sought to compare investigator reports (IRs) to a Clinical Events Committee (CEC) and the impact of SCTI (Standardized Clinical Trial Initiative) criteria. METHODS: In the EMPEROR-Reduced trial, the authors compared IRs to the CEC for concordance; treatment effect on primary composite outcome events; and the components first event hospitalization primarily for HF or cardiovascular mortality (CVM), prognosis after hospitalization for heart failure (HHF), total HHFs, and trial duration with and without SCTI criteria. RESULTS: The CEC confirmed 76.3% of IR events for the primary outcome (CVM: 89.1%; HHF: 73.7%). The HR for treatment effect did not differ between adjudication methods for the primary outcome (IR: 0.75 [95% CI: 0.66-0.85]; CEC: 0.75 [95% CI: 0.65-0.86]), its components, or total HHFs. The prognosis after first HHF for all-cause mortality and CVM also did not differ between IR or CEC. Interestingly, IR primary HHF with different CEC primary cause had the highest subsequent fatal event rate. Full SCTI criteria were present in 90% of CEC HHFs-with a similar treatment effect to non-SCTI. The IR primary event reached the protocol target number (841) 3 months earlier than CEC (4 months with full SCTI criteria). CONCLUSIONS: Investigator adjudication is an alternative to a CEC with similar accuracy and faster event accumulation. The use of granular (SCTI) criteria did not improve trial performance. Finally, our data suggest that consideration be given to broadening the HHF definition to include "for or with" worsening disease. (Empagliflozin Outcome Trial in Patients With Chronic Heart Failure With Reduced Ejection Fraction [EMPEROR-Reduced]; NCT03057977).

Right Ventricular Free Wall Strain and Effect of Defibrillator Implantation in Patients With Nonischemic Systolic Heart Failure.

BACKGROUND: Patients with nonischemic systolic heart failure have an increased risk of malignant ventricular arrhythmias and sudden cardiovascular death. Because the risk is less pronounced than for patients with ischemic cause of heart failure more discriminating tools are needed to identify patients most likely to benefit from implantable cardioverter-defibrillator (ICD) implantation. Right ventricular (RV) dysfunction is associated with a worse prognosis, but whether RV free wall strain (RV-FWS) measured with echocardiography can identify the patients most likely to benefit from ICD implantation is not known. METHODS AND RESULTS: In this extended follow-up analysis of the Danish Study to Assess the Efficacy of ICDs in Patients with Non-ischemic Systolic Heart Failure on Mortality (DANISH) trial, RV-FWS was measured with echocardiography in 445 patients before randomization. RV dysfunction was defined as an RV-FWS of greater than -20%. The primary end point was all-cause mortality. The median RV-FWS was -18% (quartiles -23% to -14%), and RV dysfunction was measured in 255 patients (57%). During a median follow-up of 5.7 years, 170 patients (38%) died. There was a statistically significant interaction between RV dysfunction and the effect of ICD implantation (P = .003), also after adjusting for known cardiovascular risk factors (P = .01). ICD implantation significantly decreased all-cause mortality in patients with RV dysfunction (hazard ratio 0.54, 95% confidence interval 0.36-0.80, P = .002), but not in patients with normal RV function (hazard ratio 1.34, 95% confidence interval 0.84-2.12, P = .22). CONCLUSIONS: In patients with nonischemic systolic heart failure, RV dysfunction on echocardiography was associated with a greater effect of ICD implantation and could be used to select patients with benefit from ICD treatment.

Myocardial fibrosis and ventricular ectopy in patients with non-ischemic systolic heart failure: results from the DANISH trial.

Patients with non-ischemic systolic heart failure (HF) have increased risk of sudden cardiovascular death (SCD). The initiation and substrate for ventricular arrhythmias remains poorly understood. Our purpose was to describe the relationship between cardiac magnetic resonance (CMR) late gadolinium enhancement (LGE) and Holter recorded ventricular arrhythmic activity. Patients from the DANISH trial underwent a Holter-recording and a CMR-scan. The presence of non-sustained ventricular tachycardia (NSVT) and premature ventricular contractions (PVC) were examined in relation to presence and amount of LGE. Outcome measures were all-cause mortality and SCD. Overall, 180 patients were included. LGE was present in 86 (47%). NSVT occurred in 72 (40%), not different according to LGE status (p = 0.65). The amount of LGE was not correlated to the occurrence of NSVT (p = 0.40). The occurrence of couplet PVCs (p = 0.997), frequent PVCs (p = 0.12), PVCs in bigemini (p = 0.29), in trigemini (p = 0.26), or in quadrimini (p = 0.35) did not differ according to LGE status. LGE was significantly associated with risk of all-cause mortality (HR 2.14; 95% CI 1.05-4.37, p = 0.04). NSVT did not increase risk of all-cause mortality in either patients with LGE (HR 1.00; 95% CI 0.46-2.16, p = 0.996) or without LGE (HR 1.37; 95% CI 0.46-4.08, p = 0.57). There was no interaction between LGE and NSVT for the risk of all-cause mortality (p = 0.62). In patients with non-ischemic systolic HF there was no relationship between the presence of LGE and NSVT or any other Holter recorded ventricular tachyarrhythmia. LGE was associated with increased risk of mortality, independent of the presence of NSVT.

Efficacy of Implantable Cardioverter Defibrillator in Nonischemic Systolic Heart Failure According to Sex: Extended Follow-Up Study of the DANISH Trial.

BACKGROUND: Men and women may respond differently to certain therapies for heart failure with reduced ejection fraction, including implantable cardioverter defibrillators (ICD). In an extended follow-up study of the DANISH trial (Danish Study to Assess the Efficacy of ICDs in Patients With Non-Ischemic Systolic Heart Failure on Mortality), adding 4 years of additional follow-up, we examined the effect of ICD implantation according to sex. METHODS: In the DANISH trial, 1116 patients with nonischemic systolic heart failure were randomized to receive an ICD (N=556) or usual clinical care (N=550). The primary outcome was all-cause mortality. RESULTS: Of the 1116 patients randomized in the DANISH trial, 307 (27.5%) were women. During a median follow-up of 9.5 years, women had a lower associated rate of all-cause mortality (hazard ratio [HR], 0.60 [95% CI, 0.47-0.78]) cardiovascular death (HR, 0.62 [95% CI, 0.46-0.84]), nonsudden cardiovascular death (HR, 0.59 [95% CI, 0.42-0.85]), and a numerically lower rate of sudden cardiovascular death (HR, 0.70 [95% CI, 0.40-1.25]), compared with men. Compared with usual clinical care, ICD implantation did not reduce the rate of all-cause mortality, irrespective of sex (men, HR, 0.85 [95% CI, 0.69-1.06]; women, HR, 0.98 [95% CI, 0.64-1.50]; Pinteraction=0.51). In addition, sex did not modify the effect of ICD implantation on sudden cardiovascular death (men, HR, 0.57 [95% CI, 0.36-0.92]; women, HR, 0.68 [95% CI, 0.26-1.77]; Pinteraction=0.76). CONCLUSIONS: In patients with nonischemic systolic heart failure, ICD implantation did not provide an overall survival benefit, but reduced sudden cardiovascular death, irrespective of sex. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT00542945.

Electrocardiographic characteristics of trained and untrained standardbred racehorses.

BACKGROUND: Long-term exercise induces cardiac remodeling that potentially influences the electrical properties of the heart. HYPOTHESIS/OBJECTIVES: We assessed whether training alters cardiac conduction in Standardbred racehorses. ANIMALS: Two hundred one trained and 52 untrained Standardbred horses. METHODS: Cross-sectional study. Resting ECG recordings were analyzed to assess heart rate (HR) along with standard ECG parameters and for identification of atrial and ventricular arrhythmias. An electrophysiological study was performed in 13 horses assessing the effect of training on sinoatrial (SA) and atrioventricular (AV) nodal function by sinus node recovery time (SNRT) and His signal recordings. Age and sex adjustments were implemented in multiple and logistic regression models for comparison. RESULTS: Resting HR in beats per minute (bpm) was lower in trained vs untrained horses (mean, 30.8 ± 2.6 bpm vs 32.9 ± 4.2 bpm; P = .001). Trained horses more often displayed second-degree atrioventricular block (2AVB; odds ratio, 2.59; P = .04). No difference in SNRT was found between groups (n = 13). Mean P-A, A-H, and H-V intervals were 71 ± 20, 209 ± 41, and 134 ± 41 ms, respectively (n = 7). We did not detect a training effect on AV-nodal conduction intervals. His signals were present in 1 horse during 2AVB with varying H-V interval preceding a blocked beat. CONCLUSIONS AND CLINICAL IMPORTANCE: We identified decreased HR and increased frequency of 2AVB in trained horses. In 5 of 7 horses, His signal recordings had variable H-V intervals within each individual horse, providing novel insight into AV conduction in horses.

Electrocardiographic Findings, Arrhythmias, and Left Ventricular Involvement in Familial ST-Depression Syndrome.

BACKGROUND: Familial ST-depression syndrome is an inherited disease characterized by persistent, nonischemic ST-deviations, and risk of arrhythmias and heart failure. We aimed at further characterizing the ECG, arrhythmias, and structural characteristics associated with this novel syndrome. METHODS: Retrospective analysis of data from consecutive families with familial ST-depression Syndrome in Denmark. ECG features, prevalence and type of arrhythmias, occurrence of systolic dysfunction, and medium-term outcome were analyzed. RESULTS: Forty affected individuals (43% men; mean age at diagnosis 49.1 years) from 14 apparently unrelated families with ≥2 affected members were included. Autosomal dominant inheritance was observed in all families. The ECG phenotype seemed to develop in prepuberty and the ST-deviations were persistent and most pronounced in leads V4/V5/II, respectively. Serial ECG analyses showed stable to slow progression of the ECG phenotype. Exercise accentuated the ST-deviations with a maximum difference between rest/stress (mean) of -117 µV in lead V5. During a mean follow-up of 9.3±7.1 years 5 (13%) patients developed sustained ventricular arrhythmias or (aborted) sudden cardiac death, 10 (25%) developed atrial fibrillation, 2 (5%) other supraventricular arrhythmias, and 10 (25%) were diagnosed with left ventricular ejection fraction ≤50%. The ventricular arrhythmias were polymorphic with relatively short-coupled premature ventricular contractions at onset (300-360 ms); no QT prolongation was observed. Seven patients had at least one catheter ablation; 5 for supraventricular arrhythmias and 2 for ventricular arrhythmias. Males experienced more arrhythmic end points than females (P<0.01). CONCLUSIONS: The familial ST-depression ECG phenotype is stable to slowly progressive after medium-term follow-up. Clinically, both supra- and ventricular arrhythmias are common; as are some degree of left ventricular systolic dysfunction. Familial ST-depression represent a novel inherited cause of polymorphic ventricular tachycardia.

NT-proBNP and ICD in Nonischemic Systolic Heart Failure: Extended Follow-Up of the DANISH Trial.

OBJECTIVES: In this extended follow-up study of the DANISH (Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators in Patients with Non-ischemic Systolic Heart Failure on Mortality) trial, adding 4 years of additional follow-up, we examined the effect of implantable cardioverter-defibrillator (ICD) implantation according to baseline N-terminal pro-B-type natriuretic peptide (NT-proBNP) level. BACKGROUND: In the DANISH trial, NT-proBNP level at baseline appeared to modify the response to ICD implantation. METHODS: In the DANISH trial, 1,116 patients with nonischemic systolic HF were randomized to receive an ICD (N = 556) or usual clinical care (N = 550). Outcomes were analyzed according to NT-proBNP levels (below/above median) at baseline. The primary outcome was death from any cause. RESULTS: All 1,116 patients in the DANISH trial had an available NT-proBNP measurement at baseline (median: 1,177 pg/mL; range: 200-22,918 pg/mL). There was a trend toward a reduction in all-cause death with ICD implantation, compared with usual clinical care, in patients with NT-proBNP levels lower than the median (HR: 0.75 [95% CI: 0.55-1.03]), but not in those with higher NT-proBNP levels (HR: 0.95 [95% CI: 0.74-1.21]) (Pinteraction = 0.28). Similarly, ICD implantation significantly reduced the rate of cardiovascular (CV) and sudden cardiovascular death (SCD) in patients with NT-proBNP levels lower than the median (CV death, HR: 0.69 [95% CI: 0.47-1.00]; SCD, HR: 0.37 [95% CI: 0.19-0.75]), but not in those with higher levels (CV death, HR: 0.94 [95% CI: 0.70-1.25]; SCD, HR: 0.86 [95% CI: 0.49-1.51]) (Pinteraction = 0.20 and 0.08 for CV death and SCD, respectively). CONCLUSIONS: Lower baseline NT-proBNP levels could identify patients with nonischemic systolic HF who may derive benefit from ICD implantation. (Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators in Patients with Non-ischemic Systolic Heart Failure on Mortality [DANISH]; NCT00542945).

Effect of implantable cardioverter-defibrillators in patients with non-ischaemic systolic heart failure and concurrent coronary atherosclerosis.

AIMS: Prophylactic implantable cardioverter-defibrillators (ICD) reduce mortality in patients with ischaemic heart failure (HF), whereas the effect of ICD in patients with non-ischaemic HF is less clear. We aimed to investigate the association between concomitant coronary atherosclerosis and mortality in patients with non-ischaemic HF and the effect of ICD implantation in these patients. METHODS AND RESULTS: Patients were included from DANISH (Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators in Patients with Non-Ischaemic Systolic Heart Failure on Mortality), randomizing patients to ICD or control. Study inclusion criteria for HF were left ventricular ejection fraction ≤ 35% and increased levels (>200 pg/mL) of N-terminal pro-brain natriuretic peptide. Of the 1116 patients from DANISH, 838 (75%) patients had available data from coronary angiogram and were included in this subgroup analysis. We used Cox regression to assess the relationship between coronary atherosclerosis and mortality and the effect of ICD implantation. Of the included patients, 266 (32%) had coronary atherosclerosis. Of these, 216 (81%) had atherosclerosis without significant stenoses, and 50 (19%) had significant stenosis. Patients with atherosclerosis were significantly older {67 [interquartile range (IQR) 61-73] vs. 61 [IQR 54-68] years; P < 0.0001}, and more were men (77% vs. 70%; P = 0.03). During a median follow-up of 64.3 months (IQR 47-82), 174 (21%) of the patients died. The effect of ICD on all-cause mortality was not modified by coronary atherosclerosis [hazard ratio (HR) 0.94; 0.58-1.52; P = 0.79 vs. HR 0.82; 0.56-1.20; P = 0.30], P for interaction = 0.67. In univariable analysis, coronary atherosclerosis was a significant predictor of all-cause mortality [HR, 1.41; 95% confidence interval (CI), 1.04-1.91; P = 0.03]. However, this association disappeared when adjusting for cardiovascular risk factors (age, gender, diabetes, hypertension, smoking, and estimated glomerular filtration rate) (HR 1.05, 0.76-1.45, P = 0.76). CONCLUSIONS: In patients with non-ischaemic systolic heart failure, ICD implantation did not reduce all-cause mortality in patients either with or without concomitant coronary atherosclerosis. The concomitant presence of coronary atherosclerosis was associated with increased mortality. However, this association was explained by other risk factors.

Comparison of the Anterior Septal Line and Mitral Isthmus Line for Perimitral Atrial Flutter Ablation Using Robotic Magnetic Navigation.

BACKGROUND: Perimitral atrial flutter (PMAFL) is one of the most common macro-reentrant left atrial tachycardias. Mitral isthmus (MI) linear ablation is a common strategy for the treatment of PMAFLs, and anterior septum (AS) linear ablation has emerged as a novel ablation approach. We aimed at assessing the effectiveness of AS linear ablation using robotic magnetic navigation for PMAFL ablation. METHODS: In this retrospective study, a total of 36 consecutive patients presented with AFL as the unique arrhythmia or accompanied with atrial fibrillation (AF) who underwent catheter ablation were enrolled. Patients were classified into two groups according to the different ablation strategies, the MI line group (10 patients) and the AS line group (26 patients). RESULTS: The clinical baseline characteristics of patients in the two groups were nearly identical. There were no significant differences in procedure time (148.7 ± 46.1 vs. 123.2 ± 30.1 min, P=0.058) or radiofrequency ablation time (25.9 ± 11.4 vs. 23.5 ± 12.6 min) between the two groups. Fluoroscopy time was longer in the MI line group (8.0 ± 4.4 vs. 5.1 ± 2.7 min, P=0.024), and the acute success rate was higher in the AS line group versus the MI line group (96.2% vs. 70%, P=0.025). The long-term freedom from arrhythmia survival rate was higher in the AS line group (73%) than in the MI line group (40%) after a mean follow-up time of 37.4 months with a 3-month blanking period (P=0.049). CONCLUSIONS: AS linear ablation is an effective and safe strategy for PMAFL ablation using robotic magnetic navigation.

Long-Term Follow-Up of DANISH (The Danish Study to Assess the Efficacy of ICDs in Patients With Nonischemic Systolic Heart Failure on Mortality).

BACKGROUND: DANISH (The Danish Study to Assess the Efficacy of Implantable Cardioverter Defibrillators [ICDs] in Patients With Nonischemic Systolic Heart Failure on Mortality) found that primary-prevention ICD implantation was not associated with an overall survival benefit in patients with nonischemic systolic heart failure during a median follow-up of 5.6 years, although there was a beneficial effect on all-cause mortality in patients ≤70 years. This study presents an additional 4 years of follow-up data from DANISH. METHODS: In DANISH, 556 patients with nonischemic systolic heart failure were randomized to receive an ICD and 560 to receive usual clinical care and followed until June 30, 2016. In this long-term follow-up study, patients were followed until May 18, 2020. Analyses were conducted for the overall population and according to age (≤70 and >70 years). RESULTS: During a median follow-up of 9.5 years (25th-75th percentile, 7.9-10.9 years), 208/556 patients (37%) in the ICD group and 226/560 patients (40%) in the control group died. Compared with the control group, the ICD group did not have significantly lower all-cause mortality (hazard ratio [HR] 0.89, [95% CI, 0.74-1.08]; P = 0.24). In patients ≤70 years (n = 829), all-cause mortality was lower in the ICD group than the control group (117/389 [30%] versus 158/440 [36%]; HR, 0.78 [95% CI, 0.61-0.99]; P = 0.04), whereas in patients >70 years (n = 287), all-cause mortality was not significantly different between the ICD and control group (91/167 [54%] versus 68/120 [57%]; HR, 0.92 [95% CI, 0.67-1.28]; P = 0.75). Cardiovascular death showed similar trends (overall, 147/556 [26%] versus 164/560 [29%]; HR, 0.87 [95% CI, 0.70-1.09]; P = 0.20; ≤70 years, 87/389 [22%] versus 122/440 [28%]; HR, 0.75 [95% CI, 0.57-0.98]; P = 0.04; >70 years, 60/167 [36%] versus 42/120 [35%]; HR, 0.97 [95% CI, 0.65-1.45]; P = 0.91). The ICD group had a significantly lower incidence of sudden cardiovascular death in the overall population (35/556 [6%] versus 57/560 [10%]; HR, 0.60 [95% CI, 0.40-0.92]; P = 0.02) and in patients ≤70 years (19/389 [5%] versus 49/440 [11%]; HR, 0.42 [95% CI, 0.24-0.71]; P = 0.0008), but not in patients >70 years (16/167 [10%] versus 8/120 [7%]; HR, 1.34 [95% CI, 0.56-3.19]; P = 0.39). CONCLUSIONS: During a median follow-up of 9.5 years, ICD implantation did not provide an overall survival benefit in patients with nonischemic systolic heart failure. In patients ≤70 years, ICD implantation was associated with a lower incidence of all-cause mortality, cardiovascular death, and sudden cardiovascular death. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00542945.

Periodic Repolarization Dynamics Identifies ICD Responders in Nonischemic Cardiomyopathy: A DANISH Substudy.

BACKGROUND: Identification of patients with nonischemic cardiomyopathy who may benefit from prophylactic implantation of a cardioverter-defibrillator. We hypothesized that periodic repolarization dynamics (PRD), a marker of repolarization instability associated with sympathetic activity, could be used to identify patients who will benefit from prophylactic implantable cardioverter defibrillator (ICD) implantation. METHODS: We performed a post hoc analysis of DANISH (Danish ICD Study in Patients With Dilated Cardiomyopathy), in which patients with nonischemic cardiomyopathy, left ventricular ejection fraction (LVEF) ≤35%, and elevated NT-proBNP (N-terminal probrain natriuretic peptides) were randomized to ICD implantation or control group. Patients were included in the PRD substudy if they had a 24-hour Holter monitor recording at baseline with technically acceptable ECG signals during the night hours (00:00-06:00). PRD was assessed using wavelet analysis according to previously validated methods. The primary end point was all-cause mortality. Cox regression models were adjusted for age, sex, NT-proBNP, estimated glomerular filtration rate, LVEF, atrial fibrillation, ventricular pacing, diabetes, cardiac resynchronization therapy, and mean heart rate. We proposed PRD ≥10 deg2 as an exploratory cut-off value for ICD implantation. RESULTS: A total of 748 of the 1116 patients in DANISH qualified for the PRD substudy. During a mean follow-up period of 5.1±2.0 years, 82 of 385 patients died in the ICD group and 85 of 363 patients died in the control group (P=0.40). In Cox regression analysis, PRD was independently associated with mortality (hazard ratio [HR], 1.28 [95% CI, 1.09-1.50] per SD increase; P=0.003). PRD was significantly associated with mortality in the control group (HR, 1.51 [95% CI, 1.25-1.81]; P<0.001) but not in the ICD group (HR, 1.04 [95% CI, 0.83-1.54]; P=0.71). There was a significant interaction between PRD and the effect of ICD implantation on mortality (P=0.008), with patients with higher PRD having greater benefit in terms of mortality reduction. ICD implantation was associated with an absolute mortality reduction of 17.5% in the 280 patients with PRD ≥10 deg2 (HR, 0.54 [95% CI, 0.34-0.84]; P=0.006; number needed to treat=6), but not in the 468 patients with PRD <10 deg2 (HR, 1.17 [95% CI, 0.77-1.78]; P=0.46; P for interaction=0.01). CONCLUSIONS: Increased PRD identified patients with nonischemic cardiomyopathy in whom prophylactic ICD implantation led to significant mortality reduction.