2012 ACCF/AHA/HRS Focused Update Incorporated Into the ACCF/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities

Abstract

*The 2012 writing group members were required to recuse themselves from voting on sections to which their specific relationships with industry and other entities may apply; see Appendix 4 for recusal information.

Rationale and design of the AdaptResponse trial: a prospective randomized study of cardiac resynchronization therapy with preferential adaptive left ventricular‐only pacing

“…Despite the overall efficacy of CRT in reducing morbidity and mortality endpoints in patients with HF with systolic dysfunction and ventricular dyssynchrony, its effect remains largely heterogeneous, with patients showing a varying degree of clinical benefit 1, 2, 3, 4, 5. In this context, optimization of the device settings is a logical priority of current device‐related research activity.…”

“…Cardiac resynchronization therapy (CRT) is recommended by current guidelines for the treatment of patients with symptomatic heart failure (HF), impaired left ventricular (LV) systolic function, and an electrocardiogram (ECG) which displays evidence of electrical dyssynchrony,1, 2 with established effects on morbidity and mortality 3, 4. However, in spite of the overall beneficial effects of CRT, no early clinical improvement is observed in approximately 30% of CRT recipients 3, 5…”

Mechanical dyssynchrony with phase analysis of gated SPECT: Nap time is over

“…6 Still, 28% (16/58) of ''ideal guidelines candidates'' did not respond. While the Ushape contraction pattern identified a subgroup that responded almost entirely 90%, still around 50% of those with non-U-shape contract pattern (almost 29% of the entire cohort, 17/58) responded.…”

“…Shortly after, the 2012 guidelines for CRT implantation were updated and recommended CRT for patients with EF B 35%, NYHA class C II with LBBB, and QRS C 150 ms (the only class I indication) as compared to a QRS threshold C 120-130 ms with 2008 guidelines. 6 The more stringent QRS threshold for CRT implementation was meant to choose patients with greater electrical dyssynchrony, thus greater mechanical dyssynchrony, and therefore those with higher chance of CRT restoring synchronicity of myocardial contraction. However, electrical and mechanical dyssynchrony are not interchangeable, 7,8 which explains in part the remaining high rate of non-responders.…”

Usefulness of Testing for Coronary Artery Spasm and Programmed Ventricular Stimulation in Survivors of Out-of-Hospital Cardiac Arrest

“…8 However, it remains as an important unsolved clinical issue whether ICD should be indicated for all patients with OHCA, regardless of the underlying mechanisms involved. 9 In particular, the indication of ICD for the secondary prevention of lethal VAs because of CAS is controversial because CAS could be effectively suppressed by optical medications with calcium channel blockers (CCBs). [10][11][12][13] In the present study, we, thus, examined the long-term prognosis of patients with OHCA classified based on the results of the dual induction tests for CAS and lethal VAs and evaluated the necessity of ICD by the underlying mechanisms involved.…”