Acute contractile recovery extent during biventricular pacing is not associated with follow-up in patients undergoing
Federica DeVecchi1, Emanuela Facchini1, Anna Degiovanni1
1Clinical Cardiology, Università del Piemonte Orientale, Department of Translational Medicine, Azienda Ospedaliero Universitaria "Maggiore della Carità", Corso Mazzini 28, 28100 Novara, Italy.
Insights
Cardiac Resynchronization Therapy (CRT) acute contractile response does not predict long-term outcomes. Baseline QRS duration and left ventricular diastolic volume are key predictors of CRT patient prognosis.
Area of Science:
- Cardiology
- Electrophysiology
- Heart Failure Management
Background:
- Contractility assessed by dobutamine infusion correlates with reverse remodeling post-CRT.
- The predictive capacity of this method for long-term clinical response remains debated.
Purpose of the Study:
- To determine if acute inotropic response to biventricular stimulation (CRT on) predicts long-term CRT clinical effects.
- Comparison made against AAI-VVI right pacing (CRT off) at implantation.
Main Methods:
- Assessed acute changes in left ventricular (LV) elastance (Ees), arterial elastance (Ea), and Ees/Ea in 98 patients.
- Related these elastance parameters and baseline characteristics (e.g., QRS duration, LV diastolic volume) to 3-year death or rehospitalization.
- Utilized force-frequency relation, LV volumes, and continuous noninvasive blood pressure measurements.
Main Results:
- CRT significantly increased the Ees slope, with no Ea change and a modest Ees/Ea increase.
- Neither acute elastance changes nor baseline elastance values predicted long-term outcomes.
- Only baseline ventricular diastolic volume and QRS duration predicted death or rehospitalization.
Conclusions:
- Acute contractile recovery in CRT patients does not correlate with 3-year prognosis.
- Baseline QRS duration and LV diastolic volume are significant predictors of death or rehospitalization in CRT patients.
Background:
It has been reported that contractility, as assessed using dobutamine infusion, is independently associated with reverse remodeling after CRT. Controversy, however, exists about the capacity of this approach to predict a long-term clinical response. This study's purpose was to assess whether long-term CRT clinical effects can be predicted according to acute inotropic response induced by biventricular stimulation (CRT on), as compared with AAI-VVI right stimulation pacing mode (CRT off), quantified at the time of implantation.
Methods:
In 98 patients (ejection fraction 29 ± 10%), acute changes in left ventricular (LV) elastance (Ees), arterial elastance (Ea), and Ees/Ea, as assessed from slope changes of the force-frequency relation obtained when the heart rate increased, and also assessed while measuring triplane LV volumes and continuous noninvasive blood pressure, were related to death or rehospitalization during a 3-year follow-up. Other covariances tested were age, gender, disease etiology, QRS duration, amount of mitral regurgitation, LV diastolic volume, ejection fraction, and the degree of asynchrony and longitudinal strain at baseline.
Results:
There was a marked increment in the Ees slope with CRT (interaction P = 0.004), no Ea change, and modest Ees/Ea increase (interaction P < 0.05). In Cox analysis, however, neither slope changes nor baseline values of Ees, Ea, and Ees/Ea were associated with long-term follow-up. Only ventricular diastolic volume (direct relation P = 0.002) and QRS duration (inverse relation P = 0.009) predicted death/rehospitalization.
Conclusions:
Acute contractile recovery in CRT patients is not associated with 3 years prognosis. Instead, death or rehospitalization can be predicted from QRS duration and LV diastolic volume at baseline.
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