Single lead atrial vs. dual chamber pacing in sick sinus syndrome: extended register-based follow-up in the DANPACE trial.

AIMS: The DANPACE trial randomized patients with sick sinus syndrome (SSS) to single lead atrial (AAIR) or dual chamber (DDDR) pacemaker (PM). After 5 years follow-up, no difference in overall survival, stroke or heart failure (HF) was observed, whereas risk of atrial fibrillation (AF) and PM reoperation were increased in the AAIR group. The present study aimed to investigate very long term risk of death, AF hospitalization, stroke, HF and rate of change in pacing mode using national register-based data. METHODS AND RESULTS: The study population consisted of all 1384 patients included at Danish PM centres in the DANPACE trial randomized to AAIR (n = 696) or DDDR (n = 688). Long-term follow-up data was obtained from Danish national registers. Analysis was intention-to-treat. results: During mean follow-up of 8.9 years, 413 patients (59.3%) died in the AAIR-group compared to 367 (53.3%) in the DDDR-group (adjusted hazard ratio 1.03; 95% confidence interval 0.90-1.19; P = 0.65). We observed no difference in risk of AF hospitalization, stroke or HF. During extended follow-up, annual rate of pacing mode change to DDDR in the AAIR group was 4.5%, and higher than the 2.3% observed during trial conduct. CONCLUSION: This register-based long-term follow-up study indicates that there is no difference in mortality among patients with SSS randomized to AAIR or DDDR pacing, even with very long follow-up. Nor is there any difference in risk of AF hospitalization, stroke or HF. The higher rate of pacing mode-change to DDDR in the AAIR group suggests a different management of patients with an AAIR PM after the DANPACE trial.

Observed change in peak oxygen consumption after aortic valve replacement and its predictors.

OBJECTIVE: To assess the change in peak oxygen consumption (pVO2) and determine its outcome predictors after aortic valve replacement (AVR) for aortic stenosis (AS). METHODS: Patients with AS and preserved left ventricular ejection fraction who were referred for single AVR had cardiopulmonary exercise testing prior to and 9 months post-AVR. Predictors of outcome for pVO2 were determined by multivariate linear and logistic regression analyses. A significant change in pVO2 was defined as a relative change that was more than twice the coefficient of repeatability by test-retest (>10%). RESULTS: The pre-AVR characteristics of the 37 study patients included the following: median age (range) 72 (46-83) years, aortic valve area index (AVAI) 0.41 (SD 0.11) cm(2)/m(2), mean gradient (MG) 49.1 (SD 15.3) mm Hg and New York Heart Association (NYHA)≥II 27 (73%). Pre-AVR and post-AVR mean pVO2 was 18.5 and 18.4 mL/kg/m(2) (87% of the predicted), respectively, but the change from pre-AVR was heterogeneous. The relative change in pVO2 was positively associated with the preoperative MG (ß=0.50, p=0.001) and negatively associated with brain natriuretic peptide > upper level of normal according to age and gender (ß=-0.40, p=0.009). A relative increase in pVO2 exceeding 10% was found in 9 (24%), predicted by lower pre-AVR AVAI (OR 0.18; 95% CI 0.04 to 0.82, p=0.027) and lower peak O2 pulse (OR 0.94; 95% CI 0.88 to 0.99, p=0.045). Decreases in pVO2 exceeding 10% were found in 11 (30%) and predicted by lower MG (OR 0.93; 95% CI 0.86 to 0.99, p=0.033). CONCLUSIONS: Change in pVO2 was heterogeneous. Predictors of favourable and unfavourable outcomes for pVO2 were identified.

Cardiopulmonary Exercise Testing in Patients with Asymptomatic or Equivocal Symptomatic Aortic Stenosis: Feasibility, Reproducibility, Safety and Information Obtained on Exercise Physiology.

OBJECTIVE: The aim of this study was to determine the feasibility, reproducibility, safety and information obtained on exercise physiology from cardiopulmonary exercise testing (CPX) in patients with aortic stenosis. METHODS: Patients with an aortic valve area (AVA) <1.3 cm2 who were judged asymptomatic or equivocal symptomatic underwent CPX and an inert gas rebreathing test. Only those where comprehensive evaluation of CPX results indicated haemodynamic compromise from aortic stenosis were referred for valve replacement. RESULTS: The mean patient age was 72 (±9) years; an AVA index <0.6 cm2/m2 and equivocal symptomatic status were found in 90 and 70%, respectively. CPX was feasible in 130 of the 131 patients. The coefficients of repeatability by test-retest were 5.4% (pVO2) and 4.6% (peak O2 pulse). A pVO2 <83% of the expected was predicted by a lower stroke volume at exercise, lower peak heart rate and FEV1, and higher VE/VCO2, but not by AVA index. Equivocal symptomatic status and a low gradient but high valvulo-arterial impedance were associated with a lower pVO2, but not with an inability to increase stroke volume. In total, 18 patients were referred for valve replacement. At 1 year, no cardiovascular deaths had occurred. CONCLUSIONS: CPX was feasible and reproducible and provided comprehensive data on exercise physiology. A CPX-guided treatment strategy was safe up to 1 year.

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.

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.

Percutaneous coronary intervention without onsite cardiac surgery.

INTRODUCTION: Danish health authorities have major concerns with regard to the risk and the quality of care of percutaneous coronary intervention (PCI) without onsite cardiac surgery. We report the results of the first Danish PCI centre without onsite cardiac surgery. MATERIAL AND METHODS: A total of 245 patients underwent 254 elective PCIs during a six-month study period. The outcome measures were treatment latency, health care costs, mortality rate, major adverse cardiovascular events, symptom relief and quality-of-life at six-month follow-up. RESULTS: The median treatment latency was reduced from 28 to no days (p < 0.05) for patients with stable disease, and from seven to no days (p < 0.05) for patients with unstable disease. Health care costs were reduced by 4,246,652 DKK. The six-month mortality was 0.0% versus a predicted 0.4% New York State PCI-score in patients with stable disease, and a 1.4% observed study score versus a predicted 6.4% GRACE-score in patients with unstable disease. No patients required emergency bypass surgery. At six months, five myocardial infarctions (two periprocedural and two subacute stent thromboses), three restenoses and no in-stent restenosis had occurred, while angina was absent or reduced in 92% and quality-of-life had improved in 73% of the patients. CONCLUSION: Local PCI without onsite cardiac surgery was safe, quality of care was increased, health care costs were reduced and patient-perceived treatment effect was excellent.