The Utility of Ambulatory Electrocardiographic Monitoring for Detecting Silent Arrhythmias and Clarifying Symptom Mechanism in an Elderly Urban Popula

Citation : Kathleen T. Hickey, James Reiffel, Robert R. Sciacca, William Whang, Angelo Biviano, Maurita Baumeister, Carmen Castillo, Jyothi Talathothi, Hasan Garan.The Utility of Ambulatory Electrocardiographic Monitoring for Detecting Silent Arrhythmias and Clarifying Symptom Mechanism in an Elderly Urban Population with Heart Failure and Hypertension: Clinical Implications .JAFIB.2010 May;Volume 1 Issue(12): 663-674.

Background: Atrial and ventricular tachyarrhythmias, including atrial fibrillation (AF) as well as bradyarrhythmias have been well documented in elderly and generally symptomatic patients with heart failure (HF) and/or hypertension (HTN), most often using 24 hour continuous monitoring. However, the frequency of these arrhythmias, including silent as well as symptomatic, as assessed by more prolonged monitoring, the relationship between symptoms in patients with HF and/or HTN and an underlying arrhythmia, and the association of arrhythmias including those that are silent with subsequent cardiac events has not been well defined in patients 65 years or older with HF and other cardiovascular risk factors. Importantly in such patients, AF, even if symptomatic, would yield a CHADS2 score indicative of anticoagulation.

Objective: A pilot study to assess the potential value of 2 weeks of out-patient, transtelephonic cardiac auto-triggered loop-monitoring for detecting arrhythmias, assessing their relationship to symptoms, predicting the risk of subsequent cardiac events, and determining if they result in therapy in an elderly, urban population living with HF.

Methods: Fifty-four subjects with a history of systolic HF and/or HTN consented to wear an auto triggered cardiac loop monitor for 2 weeks. This device captures EKG data, including silent and symptomatic arrhythmias. Subjects were requested to transmit data once daily as well as to transmit if they were symptomatic to determine if an underlying dysrhythmia was present.

Results: Mean age was 73 ± 6 years with 59% were female, 74% Hispanic, 22% black, and 4% white/other. All subjects had HF and 94% had HTN; all were in sinus rhythm at the time of enrollment. From the cardiac monitoring, 72% demonstrated ectopic atrial and ventricular activity. In addition, 1 paroxysmal episode of AF was documented, 3 people had significant non-sustained ventricular tachycardia that contributed to the placement of an internal cardioverter defibrillator (ICD), and 4 individuals underwent subsequent placement of a pacemakers for severe bradycardia/heart block (per established guidelines). The relationship between arrhythmia and symptoms was weak. These events would have otherwise gone undetected and untreated. During follow-up, 15 subjects (28%) had significant cardiac events, including one patient with a non ST segment myocardial infarction (NSTEMI) infarct due to undetected and untreated AF and one patient with symptomatic 2:1 atrial flutter. The AF and flutter patients all had CHADS2 scores appropriate for initiation of anticoagulation.

Conclusion: A substantial proportion of subjects exhibited arrhythmias during monitoring, cardiac events during follow-up and consequent therapy. This approach to arrhythmia screening appears to have sufficient merit to warrant further study.