Gunnar V.H. Jensen

Defibrillator Implantation in Patients with Nonischemic Systolic Heart Failure

BACKGROUND The benefit of an implantable cardioverter-defibrillator (ICD) in patients with symptomatic systolic heart failure caused by coronary artery disease has been well documented. However, the evidence for a benefit of prophylactic ICDs in patients with systolic heart failure that is not due to coronary artery disease has been based primarily on subgroup analyses. The management of heart failure has improved since the landmark ICD trials, and many patients now receive cardiac resynchronization therapy (CRT). METHODS In a randomized, controlled trial, 556 patients with symptomatic systolic heart failure (left ventricular ejection fraction, ≤35%) not caused by coronary artery disease were assigned to receive an ICD, and 560 patients were assigned to receive usual clinical care (control group). In both groups, 58% of the patients received CRT. The primary outcome of the trial was death from any cause. The secondary outcomes were sudden cardiac death and cardiovascular death. RESULTS After a median follow-up period of 67.6 months, the primary outcome had occurred in 120 patients (21.6%) in the ICD group and in 131 patients (23.4%) in the control group (hazard ratio, 0.87; 95% confidence interval [CI], 0.68 to 1.12; P=0.28). Sudden cardiac death occurred in 24 patients (4.3%) in the ICD group and in 46 patients (8.2%) in the control group (hazard ratio, 0.50; 95% CI, 0.31 to 0.82; P=0.005). Device infection occurred in 27 patients (4.9%) in the ICD group and in 20 patients (3.6%) in the control group (P=0.29). CONCLUSIONS In this trial, prophylactic ICD implantation in patients with symptomatic systolic heart failure not caused by coronary artery disease was not associated with a significantly lower long-term rate of death from any cause than was usual clinical care. (Funded by Medtronic and others; DANISH ClinicalTrials.gov number, NCT00542945 .).

A comparison of single-lead atrial pacing with dual-chamber pacing in sick sinus syndrome

AIMS In patients with sick sinus syndrome, bradycardia can be treated with a single-lead pacemaker or a dual-chamber pacemaker. Previous trials have revealed that pacing modes preserving atrio-ventricular synchrony are superior to single-lead ventricular pacing, but it remains unclear if there is any difference between single-lead atrial pacing (AAIR) and dual-chamber pacing (DDDR). METHODS AND RESULTS We randomly assigned 1415 patients referred for first pacemaker implantation to AAIR (n = 707) or DDDR (n = 708) pacing and followed them for a mean of 5.4 ± 2.6 years. The primary outcome was death from any cause. Secondary outcomes included paroxysmal and chronic atrial fibrillation, stroke, heart failure, and need for pacemaker reoperation. In the AAIR group, 209 patients (29.6%) died during follow-up vs. 193 patients (27.3%) in the DDDR group, hazard ratio (HR) 1.06, 95% confidence interval (CI) 0.88-1.29, P = 0.53. Paroxysmal atrial fibrillation was observed in 201 patients (28.4%) in the AAIR group vs. 163 patients (23.0%) in the DDDR group, HR 1.27, 95% CI 1.03-1.56, P = 0.024. A total of 240 patients underwent one or more pacemaker reoperations during follow-up, 156 (22.1%) in the AAIR group vs. 84 (11.9%) in the DDDR group (HR 1.99, 95% CI 1.53-2.59, P < 0.001). The incidence of chronic atrial fibrillation, stroke, and heart failure did not differ between treatment groups. CONCLUSION In patients with sick sinus syndrome, there is no statistically significant difference in death from any cause between AAIR pacing and DDDR pacing. AAIR pacing is associated with a higher incidence of paroxysmal atrial fibrillation and a two-fold increased risk of pacemaker reoperation. These findings support the routine use of DDDR pacing in these patients. CLINICAL TRIAL REGISTRATION URL http://www.clinicaltrials.gov. Unique identifier: NCT00236158.

Disease activity in inflammatory bowel disease is associated with increased risk of myocardial infarction, stroke and cardiovascular death--a Danish nationwide cohort study.

Purpose Chronic inflammatory diseases have been linked to increased risk of atherothrombotic events, but the risk associated with inflammatory bowel disease (IBD) is unclear. We therefore examined the risk of myocardial infarction (MI), stroke, and cardiovascular death in patients with IBD. Methods In a nationwide Danish population-based setting, a cohort of patients with incident IBD between 1996 and 2009 were identified in national registers. Hospitalizations with IBD as primary diagnosis, initiation of biological treatment and dispensed prescriptions of corticosteroids were all used as surrogate markers for disease activity, with flares classified as the first 120 days after diagnosis of IBD, and 120 days after a new corticosteroid prescription, biological treatment or IBD hospitalization, respectively. Continued corticosteroid prescriptions or IBD hospitalizations were defined as persistent activity, and periods free of such events were defined as remissions. Poisson regression was used to examine risk of MI, stroke, and cardiovascular death using a matched population-based comparison cohort as reference Results We identified 20,795 IBD patients with a mean age of 40.3 years that were matched according to age and sex with 199,978 controls. During the study period, there were 365 patients with MI, 454 with stroke, and 778 with cardiovascular death. Patients with IBD had an overall increased risk of MI (rate ratio [RR] 1.17 [95% confidence interval 1.05–1.31]), stroke (RR 1.15 [1.04–1.27], and cardiovascular death (RR 1.35 [1.25–1.45]). During flares and persistent IBD activity the RRs of MI increased to 1.49 (1.16–1.93) and 2.05 (1.58–2.65), the RRs of stroke to 1.53 (1.22–1.92) and 1.55 (1.18–2.04) and for cardiovascular death 2.32 (2.01–2.68) and 2.50 (2.14–2.92). In remission periods, the risk of MI, stroke and cardiovascular death was similar to controls. Conclusion Inflammatory bowel disease is associated with increased risk of MI, stroke, and cardiovascular death during periods with active disease.

Long-Term Outcome in Patients Treated With Sirolimus-Eluting Stents in Complex Coronary Artery Lesions: 3-Year Results of the SCANDSTENT (Stenting Coronary Arteries in Non-Stress/Benestent Disease) Trial

OBJECTIVES Our purpose was to evaluate the long-term use of sirolimus-eluting stents (SES) and bare-metal stents (BMS) in patients with complex coronary artery lesions. BACKGROUND Although the use of SES has proved to be effective in patients with simple coronary artery lesions, there are limited data of the long-term outcome of patients with complex coronary artery lesions. METHODS We randomly assigned 322 patients with total coronary occlusions or lesions located in bifurcations, ostial, or angulated segments of the coronary arteries to have SES or BMS implanted. RESULTS At 3 years, major adverse cardiac events had occurred in 20 patients (12%) in the SES group and in 59 patients (38%) in the BMS group (p < 0.001). Four versus 2 patients suffered a cardiac death (p = NS), and 5 versus 1 died of a noncardiac disease (p = NS) in the SES versus the BMS group. Six patients in the SES group versus 15 patients in the BMS group suffered a myocardial infarction (p < 0.05) during the 3-year observation period, and target lesion revascularization was performed in 8 patients (4.9%) versus 53 patients (33.8%), respectively (p < 0.001); of these, 4 in the SES versus 7 in the BMS group were performed between 1 and 3 years after the index treatment (p = NS). According to revised definitions, stent thrombosis occurred in 5 patients (3.1%) in the SES group and in 7 patients (4.4%) in the BMS group (p = NS); very late stent thrombosis was observed in 4 versus 1 patient. CONCLUSIONS A continued benefit was observed up to 3 years after implantation of SES in patients with complex coronary artery lesions. The rate of late adverse events was similar in the 2 groups, and stent thromboses occurred rarely after 1 year. (Sirolimus Eluting Stents in Complex Coronary Lesions [SCANDSTENT]; NCT00151658)

Atrial fibrillation in patients with sick sinus syndrome: the association with PQ-interval and percentage of ventricular pacing

AIMS In the recently published DANPACE trial, incidence of atrial fibrillation (AF) was significantly higher with single-lead atrial (AAIR) pacing than with dual-chamber (DDDR) pacing. The present analysis aimed to evaluate the importance of baseline PQ-interval and percentage of ventricular pacing (VP) on AF. METHODS AND RESULTS We analysed data on AF during follow-up in 1415 patients included in the DANPACE trial. In a subgroup of 650 patients with DDDR pacemaker, we studied whether %VP, baseline PQ-interval, and programmed atrio-ventricular interval (AVI) was associated with AF burden measured as time in mode-switch (MS) detected by the pacemaker. In the entire DANPACE study population, the incidence of AF was significantly higher in patients with baseline PQ-interval >180 ms (P< 0.001). Among 650 patients with DDDR pacemaker, telemetry data were available for 1.337 ± 786 days, %VP was 66 ± 33%, AF was detected at planned follow-up in 160 patients (24.6%), MS occurred in 422 patients (64.9%), and AF burden was marginally higher with baseline PQ-interval >180 ms (P= 0.028). No significant association was detected between %VP and %MS (Spearmans ρ 0.056, P= 0.154). %MS was not different between minimal-paced programmed AVI ≤ 100 and >100 ms (median value), respectively (P= 0.60). CONCLUSIONS The present study indicates that a longer baseline PQ-interval is associated with an increased risk of AF in patients with sick sinus syndrome. Atrial fibrillation burden is not associated with the percentage of VP or the length of the programmed AVI.

CHADS2 and CHA2DS2-VASc score to assess risk of stroke and death in patients paced for sick sinus syndrome

Objective The risk of stroke in patients with atrial fibrillation (AF) can be assessed by use of the CHADS2 and the CHA2DS2-VASc score system. We hypothesised that these risk scores and their individual components could also be applied to patients paced for sick sinus syndrome (SSS) to evaluate risk of stroke and death. Design Prospective cohort study. Settings All Danish pacemaker centres and selected centres in the UK and Canada. Patients Risk factors were recorded prior to pacemaker implantation in 1415 patients with SSS participating in the Danish Multicenter Randomized Trial on Single Lead Atrial Pacing versus Dual Chamber Pacing in Sick Sinus Syndrome (Danpace) trial. Development of stroke was assessed at follow-up visits and by evaluation of patient charts. Mortality was assessed from the civil registration system. Interventions Patients were randomised to AAIR (N=707) or DDDR pacing (N=708). Main outcome measures Stroke and death during follow-up. Results Mean follow-up was 4.3±2.5 years. In the AAIR group 6.9% patients developed stroke versus 6.1% in the DDDR group (NS). There was a significant association between CHADS2 score and the development of stroke (HR 1.41; 95% CI 1.22 to 1.64, p<0.001). CHA2DS2-VASc score was also significantly associated with stroke (HR 1.25; CI 1.12 to 1.40, p<0.001). CHADS2 score (HR 1.46; CI 1.36 to 1.56, p<0.001) and CHA2DS2-VASc score (HR 1.39; CI 1.31 to 1.46, p<0.001) were associated with mortality. Results were still significant after adjusting for AF and anticoagulation therapy. Conclusions CHADS2 and CHA2DS2-VASc score are associated with increased risk of stroke and death in patients paced for SSS irrespective of the presence of AF.

The impact of heart failure on prognosis of diabetic and non-diabetic patients with myocardial infarction: a 15-year follow-up study

Information about the occurrence of heart failure in the acute phase of myocardial infarction (MI) in diabetic patients and its impact on prognosis are sparse.

Clinical use of automatic pacemaker algorithms: results of the AUTOMATICITY registry.

AIMS Follow-up of the ever-increasing numbers of patients with implantable cardiac devices places a heavy burden on clinical departments. Device automaticity may alleviate the follow-up burden by minimizing the time for physician involvement. The aim of the prospective, multicentre AUTOMATICITY registry was to examine the performance of a subset of programmed automatic algorithms during patient follow-up and their acceptance by implanting physicians. METHODS AND RESULTS The clinical use of automatic algorithms from the Insignia pacemakers (PM; Boston Scientific, St Paul, MN, USA) was evaluated: atrial and ventricular AutoSense (sensitivity adjustment), ventricular Automatic Capture (threshold verification and output setting), AutoLifeStyle (sensor settings adjustment). The objective of the study was to assess the reprogramming rates within 12 months of implant, the reasons for reprogramming and relationship to adverse events. A total of 960 patients were enrolled in the study. The proportion of patients free from any algorithm reprogramming at 12 months was 86.1%. A total of 2736 algorithms were activated at enrolment, with 156 (5.7%) being reprogrammed in 115 patients at 12 months for any reason. Forty-nine reprogrammings (1.8%) were unintentional or related to changes in device settings such that the algorithm was no longer available, 33 (1.2%) were due to suspected sensing issues, and 22 (0.8%) were assumed related to the algorithm. The individual 12-month reprogramming-free rates were: ventricular AutoSense 94.3%, Atrial AutoSense 93.3%, AutoLifeStyle 93.9%, and Automatic Capture 95.9%. CONCLUSION The results of the AUTOMATICITY registry show that automatic measurement of key settings and automatic adjustment to optimal programming is feasible and safe. The simplicity of PM follow-up and avoidance of frequent reprogramming may contribute to a more effective use of hospital time and resources.

Prognosis of late versus early ventricular fibrillation in acute myocardial infarction

To determine the prognosis of late ventricular fibrillation (VF) after acute myocardial infarction (AMI), the length of the monitoring period after AMI was extended. All patients in this series were continuously monitored in a coronary care unit to ensure observation of all VF within 18 days of AMI. From 1977 to 1985, 4,269 patients were admitted with AMI and 413 (9.6%) had in-hospital VF. Of these 281 (6.8%) had early VF (less than 48 hours after AMI) and 132 (3.2%) had late VF (greater than or equal to 48 hours after AMI). In-hospital mortality was 50 and 54% for early and late VF, respectively (p = 0.31). Kaplan-Meier survival analysis showed better survival after discharge for patients with early versus late VF (p = 0.009) but this difference was fully explained by the presence of heart failure. Survival analysis showed the same prognosis after 1, 3 and 5 years for early and late VF, when VF was not associated with heart failure. When VF was associated with heart failure (secondary VF) early VF had a greater mortality than late VF after 2 and 5 years. Logistic regression analysis showed that heart failure (relative risk 1.9 [1.1 to 3.1]) and cardiogenic shock (relative risk 3.9 [1.8 to 8.5]) were significant risk factors for in-hospital death. Late VF compared to early VF had no prognostic implication (relative risk 1.0 [0.6 to 1.6]). For patients discharged from the hospital, risk factors were heart failure (1.8 [1.1 to 2.8]) and previous AMI (1.6 [1.3 to 2.1]).(ABSTRACT TRUNCATED AT 250 WORDS)

Waiting for a pacemaker: is it dangerous?

AIMS To determine waiting period-related morbidity, mortality, and adverse events in acute patients waiting for a permanent pacemaker (PPM). METHODS AND RESULTS A retrospective chart review of all PPM implantations in Region Zealand, Denmark, in 2009 was conducted. Patients were excluded if they were discharged from the hospital during the waiting period or referred from the outpatient department. Adverse events were tracked. Four hundred and eighty-seven PPM implantations were identified. Of these, 259 patients (53.2%) required acute PPM implantation and waited a mean of 5.1 days from PPM indication to implantation. A lack of implantation capacity was responsible for 4.5 of the waiting days. Twenty-nine patients (11.2%) developed infection while waiting, primarily urinary tract infections. Thirteen patients (5.0%) suffered non-sustained ventricular tachycardia, and eight patients (3.1%) suffered clinical cardiac arrest followed by successful resuscitation. Three patients (1.2%) died during the waiting period before successful implantation. Forty-eight patients (18.5%) received the sympathomimetic beta-adrenergic agent, isoprenaline, and seven patients (13.7%) had malignant arrhythmias or cardiac arrest, reaching statistical significance (P < 0.05). Twenty-eight patients (10.8%) had a temporary transvenous-pacing catheter applied acutely. CONCLUSIONS The patients awaited acute PPM implantations for a mean of 4.5 days because of capacity problems. Overall, 83 patients (32.0%) experienced at least one adverse event during the waiting period. The present study indicates that a waiting period is dangerous as it is associated with an increased risk of adverse events. Acute PPMs should be implanted with a 24-h pacemaker implantation service capacity.