Cardiac resynchronization therapy (CRT) decreases the morbidity and mortality in @entity1 with end-stage @entity712 . However, @entity1 selection remains challenging, because a considerable 30% to 50% do not respond. Controversy exists on the cutoff values for the QRS duration and the optimal lead location. The present study relates these parameters on an individual basis to acute pump function improvement using invasively obtained pressure-volume loops. Fifty-seven @entity1 with symptomatic end-stage @entity712 were included in our temporary biventricular stimulation study and were grouped according to the QRS duration (QRS <20 ms, QRS >= 120 ms but <150 ms, and QRS >= 150 ms). All @entity1 underwent pressure-volume loop assessment of the response to biventricular pacing, comparing the baseline measurements to both right ventricular apex pacing combined with a left ventricular lead in the posterolateral and anterolateral region of the LV. Group analysis during conventional (posterolateral and right ventricular apex) CRT did not show improvement in @entity64 work and dP/dt(max) (-2%, p = NS; and -7%; p <0.001) in the narrow QRS group but a significant increase in the intermediate (+27%, p = 0.020, and +5%, p = 0.044) and wide (+48%, p = 0.002, and +18%, p <0.001) QRS groups. CRT using the anterolateral and right ventricular apex configuration evoked a consistently lower response compared to posterolateral and right ventricular apex, resulting in a significant hemodynamic deterioration in the narrow QRS group. However, analysis on an individual basis identified 25% of @entity1 with narrow QRS duration showing possible hemodynamic benefit from CRT compared to 83% of @entity1 with intermediate and wide QRS combined. In contrast, 15% of @entity1 had deterioration by conventional (posterolateral right ventricular apex) CRT in the intermediate and wide QRS groups compared to 31% in the narrow QRS group; 19% of @entity1 could be improved by lead placement in the anterolateral rather than the posterolateral region. In conclusion, the acute hemodynamic response to CRT is generally in line with the long-term results from large randomized trials; however, the individual variation is large. The temporary biventricular stimulation protocol might aid in individual @entity1 selection and in research aiming at a reduction of nonresponders and improvement in lead positioning.

Effects of QRS duration and pacing location on pressure-volume loop evaluation of cardiac resynchronization therapy in end-stage XXXX .

@entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity64 :: ('MESH:D020521', 'Disease') :: ['stroke'] @entity712 :: ('MESH:D006333', 'Disease') :: ['heart failure']
@entity712 :: (MESH:D006333,Disease) :: ['heart failure']
