The incidence and prognostic significance of cardiac arrhythmias and conduction abnormalities in patients with acute coronary syndromes and renal dysfunction.

BACKGROUND The incidence of cardiac arrhythmias, including atrial fibrillation (AF) in chronic kidney disease, is unknown, although AF is several times more common in patients with end-stage kidney disease than in the general population. AIM To assess the incidence, types and management of cardiac arrhythmias and conduction abnormalities in patients with acute coronary syndromes (ACS) and renal dysfunction. We also evaluated the prognostic significance of arrhythmias in this patient group. METHODS We analysed 86 patients with renal dysfunction (GFR < 60 mL/min) out of 1005 patients hospitalised in our department between 2008 and 2009 for unstable angina and ST-elevation and non-ST-elevation myocardial infarction. RESULTS Cardiac arrhythmias were observed in 44 (51.1%) patients with AF being the most common (27 patients, 31.4%), predominantly in the paroxysmal form (21.4%). A total of 14 (16.3%) patients had cardiac arrhythmias requiring temporary or permanent pacing. Only 4 (4.6%) patients showed transient conduction abnormalities due to hyperkalaemia in the course of renal failure, while the remaining 10 (11.6%) patients demonstrated conduction abnormalities due to ACS. A total of 3 (3.5%) patients had other arrhythmias (atrial tachycardia, ventricular arrhythmias). During the follow-up period (mean duration: 14.3 months) 7 out of 44 patients (15.9%) with renal dysfunction and arrhythmia and 2 out of 42 patients (4.7%) without arrhythmia died (p < 0.05). CONCLUSIONS Cardiac arrhythmias occur more often in patients with ACS if renal dysfunction is also present and are associated with poor prognosis.