Stunning and cumulative left ventricular dysfunction occurs late after coronary balloon occlusion in humans insights from simultaneous coronary and left ventricular hemodynamic assessment.

OBJECTIVES

We aimed to investigate whether left ventricular (LV) stunning could be detected late after coronary occlusion when coronary flow has normalized.

BACKGROUND

Stunning and cumulative LV dysfunction after ischemia reperfusion has been clearly demonstrated in animal models but has been refuted in several angioplasty models in humans. However, these studies have assessed LV function early, during the reactive hyperemic phase, which might have augmented LV function.

METHODS

We recruited 20 male subjects with single-vessel, type A coronary disease, and normal ventricular function. We simultaneously measured LV function with a conductance catheter and coronary flow velocity with a Combowire (Volcano Therapeutics, Inc., Rancho Cordova, California) at baseline (BL), for 30 s after a low-pressure coronary balloon occlusion for 1 min and again after 30 min, before a second balloon occlusion.

RESULTS

Stunning was detected at 30 min after a 1-min balloon occlusion: stroke volume (ml) BL1: 88.4 (22.8) versus BL2: 79.4 (24.0), p = 0.04; tau (ms) BL1: 49.8 (9.0) versus BL2: 52.5 (8.9), p = 0.02, despite full recovery of coronary average peak velocity (p = 0.62). A second balloon occlusion caused cumulative LV dysfunction: stroke volume (ml) BO1: 77.3 (34.6) versus BO2 64.9 (22.9), p = 0.01. Reactive hyperemia significantly augmented early recovery systolic function: dP/dt max 30 s: +5.8% versus 30 min - 5.4%, p = 0.0009.

CONCLUSIONS

Coronary occlusion for 1-min results in late stunning and cumulative LV dysfunction after 30 min. Reactive hyperemia augments stunned LV systolic function in early recovery.