Volumetric Response beyond Six Months of Cardiac Resynchronization Therapy and Clinical Outcome.
OBJECTIVE
Response to cardiac resynchronization therapy (CRT) is often assessed six months after implantation. Our objective was to assess the number of patients changing from responder to non-responder between six and 14 months, so-called late non-responders, and compare them to patients who were responder both at six and 14 months, so-called stable responders. Furthermore, we assessed predictive values of six and 14-month response concerning clinical outcome.


METHODS
105 patients eligible for CRT were enrolled. Clinical, laboratory, ECG, and echocardiographic parameters and patient-reported health status (Kansas City Cardiomyopathy Questionnaire [KCCQ]) were assessed before, and six and 14 months after implantation. Response was defined as ≥15% LVESV decrease as compared to baseline. Major adverse cardiac events (MACE) were registered until 24 months after implantation. Predictive values of six and 14-month response for MACE were examined.


RESULTS
In total, 75 (71%) patients were six-month responders of which 12 (16%) patients became late non-responder. At baseline, late non-responders more often had ischemic cardiomyopathy and atrial fibrillation, higher BNP and less dyssynchrony compared to stable responders. At six months, late non-responders showed significantly less LVESV decrease, and higher creatinine levels. Mean KCCQ scores of late non-responders were lower than those of stable responders at every time point, with the difference being significant at 14 months. The 14 months response was a better predictor of MACE than six months response.


CONCLUSIONS
The assessment of treatment outcomes after six months of CRT could be premature and response rates beyond might better correlate to long-term clinical outcome.
Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
Jetske
J
van 't Sant
Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
Aernoud T L
AT
Fiolet
Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
Iris A H
IA
ter Horst
Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
Maarten J
MJ
Cramer
Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands; Department of Medical and Clinical Psychology, CoRPS-Center of Research on Psychology in Somatic diseases, Tilburg University, Tilburg, The Netherlands.
Mirjam H
MH
Mastenbroek
Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
Wouter M
WM
van Everdingen
Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
Thomas P
TP
Mast
Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
Pieter A
PA
Doevendans
Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands; Department of Medical and Clinical Psychology, CoRPS-Center of Research on Psychology in Somatic diseases, Tilburg University, Tilburg, The Netherlands.
Henneke
H
Versteeg
Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands.
Mathias
M
Meine
D000368:Aged; D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects; D005260:Female; D005500:Follow-Up Studies; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D013318:Stroke Volume / Q000502:physiology*; D013599:Systole; D013997:Time Factors; D016896:Treatment Outcome