Transmitral flow propagation velocity and assessment of diastolic function during abdominal aortic aneurysm repair

In the perioperative arena, pronounced changes in cardiac loading conditions can make assessment of diastolic parameters difficult. A number of Doppler techniques have been introduced to assess perioperative diastolic function.

To compare transmitral flow propagation velocity (Vp) with other pulse-wave Doppler echocardiographic assessments of diastolic function in patients undergoing elective abdominal aortic aneurysm (AAA) resection.

A prospective observational study.

Forty-five consecutive patients undergoing elective AAA repair under general anesthesia.

Transesophageal echocardiographic examination was performed before, during, and after removal of the aortic cross-clamp (AXC). Diastolic function was categorized on the basis of the ratio of transmitral pulse-wave Doppler (PWD) into early (E) and late (A) waves and their ratio (E/A), deceleration time, and use of pulmonary venous inflow patterns to identify pseudonormal pattern. Subjects were then assessed by using the Canadian Consensus Guidelines (CCG) and on the basis of transmitral flow Vp. The correlation among methods for diagnosis of diastolic dysfunction and pseudonormal pattern was examined. Diastolic function over each of the 3 periods to assess changes during AXC was examined.

Data analysis was completed in 35 patients. The authors found excellent correlation between E/A ratio and Vp for diagnosis of diastolic dysfunction (24/25 cases) and a pseudonormal pattern (18/20 cases). The CCG methodology identified fewer cases of diastolic dysfunction than Vp (p = 0.003). The evaluation using CCG methodology could not be categorized in 15% of cases. The incidence of diastolic dysfunction increased during placement of AXC with both Vp and CCG (p < 0.05) but not by E/A ratio, and returned to baseline after removal of the AXC. Good correlation was found among all 3 methods (p < 0.05 and r > 0.5 for all).

Vp assessment identified the majority (93%) of cases of diastolic dysfunction identified by traditional methods. Furthermore, the incidence of diastolic dysfunction increased with application of the AXC but returned to baseline after removal.