Global longitudinal strain and left atrial volume index improve prediction of appropriate implantable cardioverter defibrillator therapy in hypertrophic cardiomyopathy patients.
Accurate predictors of appropriate implantable cardioverter defibrillator (ICD) therapy in hypertrophic cardiomyopathy (HCM) patients are lacking. Both left atrial volume index (LAVI) and global longitudinal strain (GLS) have been proposed as prognostic markers in HCM patients. The specific value of LAVI and GLS to predict appropriate ICD therapy in high-risk HCM patients was studied. LAVI and 2-dimensional speckle tracking-derived GLS were assessed in 92 HCM patients undergoing ICD implantation (69 % men, mean age 50 ± 14 years). During long-term follow-up, appropriate ICD therapies, defined as antitachycardia pacing and/or shock for ventricular arrhythmia, were recorded. Appropriate ICD therapy occurred in 21 patients (23 %) during a median follow-up of 4.7 (2.2-8.2) years. Multivariate analysis revealed LAVI (p = 0.03) and GLS (p = 0.04) to be independent predictors of appropriate ICD therapy. Both LAVI and GLS showed higher accuracy to predict appropriate ICD therapy compared to presence of ≥1 conventional sudden cardiac death (SCD) risk factor(s) [area under the curve 0.76 (95 % CI 0.65-0.87) and 0.65 (95 % CI 0.54-0.77) versus 0.52 (95 % CI 0.43-0.58) respectively, p < 0.001]. No patient with both LAVI <34 mL/m(2) and GLS <-14 % experienced appropriate ICD therapy. Assessment of both LAVI and GLS on top of conventional SCD risk factors provided incremental clinical predictive value for appropriate ICD therapy, as shown by likelihood ratio test (p < 0.001) and integrated discrimination improvement index (0.17, p < 0.001). LAVI and GLS provide high negative predictive value for appropriate ICD therapy in high-risk HCM patients. Additionally to conventional SCD risk factors, both parameters may be useful to optimize criteria and timing for ICD implantation in these patients.
Department of Cardiology, Leiden University Medical Centre, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands, pdebonnaire@hotmail.com.
Philippe
P
Debonnaire
Joep
J
Thijssen
Darryl P
DP
Leong
Emer
E
Joyce
Spyridon
S
Katsanos
Georgette E
GE
Hoogslag
Martin J
MJ
Schalij
Douwe E
DE
Atsma
Jeroen J
JJ
Bax
Victoria
V
Delgado
Nina Ajmone
NA
Marsan
D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy*; D017147:Defibrillators, Implantable; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000503:physiopathology; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012307:Risk Factors; D013318:Stroke Volume / Q000502:physiology*; D016896:Treatment Outcome; D014463:Ultrasonography