PVC induced cardiomyopathy

Revision as of 20:52, 19 April 2018 by Farbod Zahedi (talk | contribs)
Jump to navigation Jump to search


Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor-In-Chief: Farbod Zahedi Tajrishi, M.D.

Overview

PVC-induced cardiomyopathy has been a controversial subject since its introduction. The concept of the disease is mainly based on the overwhelming evidence suggesting that frequent PVCs may cause, or at least play a role in the development of a reversible form of cardiomyopathy. Although there is no clear definition for the condition, it is commonly known as either a state of decreased LVEF (<50%) in the presence of frequent PVCs that is increased by at least 15% or ≥10% or restored to more than 50% after PVC reduction therapy.[1][2] The term "frequent" is vague and not precisely explained in this definition. Different studies have considered PVC burdens of ≥10% to 29±13% as frequent, and some have suggested PVC burden >24% to be a stronger predictor for developing cardiomyopathy, although even a burden of 4% is reported to be able to cause cardiomyopathy.[1][3] [21]. [11, 22, 23 In addition to issues in the definition of PVC-induced cardiomyopathy, the mechanism for the development of this condition is not yet understood. Treatment is based on PVC suppression that is achieved either by anti-arrhythmic agents or radio-frequency catheter ablation.

Historical perspective

In 1998, a study demonstrated that treating patients with frequent PVCs ( > 20,000 per day ) and ventricular dysfunction with amiodarone could significantly improve LVEF.[4] This result led to the initial assumption that frequent PVCs might cause a reversible form of cardiomyopathy and thus, the concept of PVC-induced cardiomyopathy as a separate entity was formed. Since then, multiple studies have attempted to clarify the nature and the features of the disease. However, the mechanisms through which frequent PVCs can cause ventricular dysfunction remain mainly unknown. Initial studies suggested that PVC-induced cardiomyopathy was essentially a tachycardia-induced cardiomyopathy as seen with other arrhythmias such as atrial fibrillation.[5] This hypothesis was rejected, however, because many patients with PVC-induced cardiomyopathy had normal average heart rates.[6]

Pathophysiology

The exact pathogenesis of PVC-induced cardiomyopathy is not fully understood.

Causes and risk factors

Table 1- Evidence-based risk factors of PVC-induced cardiomyopathy[7]
Risk factors (predictors) Reports of different studies
PVC burden
PVC QRS duration
PVC coupling interval
Interpolated PVCs

Natural history, complications, and prognosis

History and symptoms

Physical exam

Electrocardiogram

Echocardiography

Treatment

Treatment for PVC-induced cardiomyopathy focuses on suppressing PVCs and reducing PVC burden, that could subsequently result in ventricular function improvement. Treatment methods include pharmacological therapy with anti-arrhythmic drugs and catheter ablation.

  • Medical therapy:

Pharmacotherapy is the first treatment option for asymptomatic or mildly symptomatic patients without any structural heart disease.[8] There are several anti-arrhythmic drugs available such as beta-blockers, calcium channel blockers, flecainide, propafenone, amiodarone or sotalol with varying effectiveness and side effects. Beta-blockers are usually considered as a first line therapy, due to their low adverse effects and potential secondary benefits. In patients with no symptoms of heart failure, non-dihydropyridine calcium channel blockers are reasonable alternatives.[9] However, these two groups have only modest efficacy in reducing PVC burden. Moreover, whether they could significantly improve LVEF is still among debate. For instance, a study reported a 36% reduction of PVC burden with beta-blockers and no effect on LVEF.[6]

Antiarrhythmic drugs are stronger PVC suppressors. Studies have demonstrated reduced PVC counts by 83% in patients treated with class I antiarrhythmics compared with 70% reduction with sotalol. Amiodarone had the highest efficacy with an 84% reduction of PVC counts. Except for amiodarone, antiarrhythmic medicarions have no role in improving survival despite their higher efficacy. Due to their adverse effects such as negative inotropic and proarrhythmic effects, they are not recommended for treating frequent PVCs in CHF patients.[10][11][12][13] Amiodarone, however, is the most effective drug to reduce PVC burden without increasing mortality rate in patients with advanced CHF. It is also effective on left ventricular function improvement.[4]

  • Ablation:

References

  1. 1.0 1.1 Baman TS, Lange DC, Ilg KJ, Gupta SK, Liu TY, Alguire C; et al. (2010). "Relationship between burden of premature ventricular complexes and left ventricular function". Heart Rhythm. 7 (7): 865–9. doi:10.1016/j.hrthm.2010.03.036. PMID 20348027.
  2. Yokokawa M, Good E, Crawford T, Chugh A, Pelosi F, Latchamsetty R; et al. (2013). "Recovery from left ventricular dysfunction after ablation of frequent premature ventricular complexes". Heart Rhythm. 10 (2): 172–5. doi:10.1016/j.hrthm.2012.10.011. PMID 23099051.
  3. Bogun F, Crawford T, Reich S, Koelling TM, Armstrong W, Good E; et al. (2007). "Radiofrequency ablation of frequent, idiopathic premature ventricular complexes: comparison with a control group without intervention". Heart Rhythm. 4 (7): 863–7. doi:10.1016/j.hrthm.2007.03.003. PMID 17599667.
  4. 4.0 4.1 Duffee DF, Shen WK, Smith HC (1998). "Suppression of frequent premature ventricular contractions and improvement of left ventricular function in patients with presumed idiopathic dilated cardiomyopathy". Mayo Clin Proc. 73 (5): 430–3. doi:10.1016/S0025-6196(11)63724-5. PMID 9581582.
  5. Ellis ER, Josephson ME (2013). "Heart failure and tachycardia-induced cardiomyopathy". Curr Heart Fail Rep. 10 (4): 296–306. doi:10.1007/s11897-013-0150-z. PMID 23963583.
  6. 6.0 6.1 Zhong L, Lee YH, Huang XM, Asirvatham SJ, Shen WK, Friedman PA; et al. (2014). "Relative efficacy of catheter ablation vs antiarrhythmic drugs in treating premature ventricular contractions: a single-center retrospective study". Heart Rhythm. 11 (2): 187–93. doi:10.1016/j.hrthm.2013.10.033. PMID 24157533.
  7. Lee AK, Deyell MW (2016). "Premature ventricular contraction-induced cardiomyopathy". Curr Opin Cardiol. 31 (1): 1–10. doi:10.1097/HCO.0000000000000236. PMID 26599061.
  8. Krittayaphong R, Bhuripanyo K, Punlee K, Kangkagate C, Chaithiraphan S (2002). "Effect of atenolol on symptomatic ventricular arrhythmia without structural heart disease: a randomized placebo-controlled study". Am Heart J. 144 (6): e10. doi:10.1067/mhj.2002.125516. PMID 12486439.
  9. WRITING COMMITTEE MEMBERS. Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE; et al. (2013). "2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines". Circulation. 128 (16): e240–327. doi:10.1161/CIR.0b013e31829e8776. PMID 23741058.
  10. Echt DS, Liebson PR, Mitchell LB, Peters RW, Obias-Manno D, Barker AH; et al. (1991). "Mortality and morbidity in patients receiving encainide, flecainide, or placebo. The Cardiac Arrhythmia Suppression Trial". N Engl J Med. 324 (12): 781–8. doi:10.1056/NEJM199103213241201. PMID 1900101.
  11. Cardiac Arrhythmia Suppression Trial II Investigators (1992). "Effect of the antiarrhythmic agent moricizine on survival after myocardial infarction". N Engl J Med. 327 (4): 227–33. doi:10.1056/NEJM199207233270403. PMID 1377359.
  12. Waldo AL, Camm AJ, deRuyter H, Friedman PL, MacNeil DJ, Pauls JF; et al. (1996). "Effect of d-sotalol on mortality in patients with left ventricular dysfunction after recent and remote myocardial infarction. The SWORD Investigators. Survival With Oral d-Sotalol". Lancet. 348 (9019): 7–12. PMID 8691967.
  13. Køber L, Torp-Pedersen C, McMurray JJ, Gøtzsche O, Lévy S, Crijns H; et al. (2008). "Increased mortality after dronedarone therapy for severe heart failure". N Engl J Med. 358 (25): 2678–87. doi:10.1056/NEJMoa0800456. PMID 18565860.