Paradoxical doppler echocardiographic parameters during recovery of left atrial contractility after spontaneous conversion from paroxysmal atrial fibrillation to sinus rhythm.

Paroxysmal atrial fibrillation (PAF) reduces atrial contractility due to atrial remodeling, but little is known about the process by which contractile function is reconstituted after spontaneous conversion to sinus rhythm (SR). A 63-year-old healthy man developed PAF. PAF persisted for 2 days before spontaneous conversion to SR. Serial echocardiograms were performed at 1, 24 h, 3/4/7 days after conversion. Longitudinal myocardial strain during the pump phase of the left atrium (LA) was generally reduced at 1 h. Normal strain of the LA was restored at 3 days with the exception of the lateral wall, where restoration was delayed until 4 days. The ratio between the mitral early and atrial diastolic velocities (E/A) at 24 h was within a pseudonormal range at 1.8, but the ratio between E and early mitral annulus velocity (e': E/e') remained normal. The E/A ratio gradually decreased until 7 days post conversion, but the E/e' ratio remained normal throughout the observation period. <Learning objective: This case demonstrates that left atrial (LA) contractility was globally suppressed in paroxysmal atrial fibrillation (AF), but showed gradual restoration following conversion to sinus rhythm. Mismatch between the E/A and E/e' were observed until LA contractility was restored. A pseudonormal pattern of the E/A was induced by reduced LA contractility, not left ventricular diastolic dysfunction. The time period over which this reduced LA contractility persists holds the potential to increase paroxysmal AF detection rates.