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Published on: August 1, 2019
Value of the paced QRS duration
Wenzhi Pan1, Yangang Su, Xue Gong
1Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China.
Journal of Cardiac Failure
|April 29, 2009
Summary
Paced QRS duration (pQRSd) can detect left ventricular dysfunction in patients paced from the right ventricular apex. A pQRSd of 200 ms demonstrates good sensitivity and specificity for identifying left ventricular systolic dysfunction.
Area of Science:
- Cardiology
- Electrophysiology
- Echocardiography
Background:
- The diagnostic value of paced QRS duration (pQRSd) for left ventricular (LV) dysfunction in patients undergoing right ventricular apex (RVA) pacing remains unevaluated.
- Assessing LV function is crucial in RVA-paced individuals.
Purpose of the Study:
- To evaluate the utility of pQRSd in detecting LV dysfunction in RVA-paced patients.
- To determine the correlation between pQRSd and echocardiographic parameters, NT-proBNP levels, and NYHA functional class.
Main Methods:
- A study cohort of 272 RVA-paced patients was analyzed, with 99 diagnosed with LV systolic dysfunction (LVSD).
- Measurements included pQRSd, echocardiographic variables, and plasma NT-proBNP levels.
- Statistical analyses explored relationships between pQRSd and clinical/echocardiographic parameters.
Main Results:
- pQRSd significantly correlated with LV dimensions, LV ejection fraction, and NT-proBNP levels (all P < .001).
- A stepwise increase in pQRSd was observed with worsening NYHA functional class (P < .001).
- A pQRSd cutoff of 200 ms showed 71.72% sensitivity and 86.71% specificity for detecting LVSD. Values >= 240 ms had 100% positive predictive value, while <180 ms excluded LVSD in >97.3% of cases.
Conclusions:
- pQRSd is a valuable marker correlated with LV structure and function in RVA-paced patients.
- A pQRSd cutoff of 200 ms provides a satisfactory balance of sensitivity and specificity for detecting LVSD in this population.
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