Diastolic dysfunction, infarct size, and exercise capacity in remote myocardial infarction: a combined approach of mitral E-wave deceleration time and color M-mode flow propagation velocity

Intraventricular Pressure Gradients in Left Ventricular Aneurysms Determined by Color M-Mode Doppler Method: An Animal Study

BACKGROUND

Left ventricular aneurysm (LVA) may affect diastolic intraventricular blood flow. Color M-mode (CMM) Doppler flow propagation patterns are abnormal in the presence of apical aneurysms. The aim of this study was to validate the accuracy of CMM echocardiography for assessing the existence and size of LVA and to determine the intraventricular pressure gradient in LVA.

METHODS

CMM of the transmitral inflow in early diastole was obtained from the apical 4-chamber view in 19 sheep. The presence of the break point where the velocity decreased abruptly in the mitral inflow (point D) was determined and the distance between the apex and point D was measured. The intraventricular pressure difference between the base and the apex was measured by a catheter while it was calculated using CMM with the Euler equation.

RESULTS

The presence of the break point D showed 84% sensitivity and 100% specificity for determining the existence of an LVA. Distance between the apex and point D correlated well with scar size. Catheter- and CMM-derived intraventricular pressure difference correlated and agreed well (y = 1.0 x -0.2, r = 0.94).

CONCLUSIONS

The point of abrupt decrease in propagation velocity of the CMM recording indicated the presence and size of LVA. Intraventricular pressure gradients were determined noninvasively by CMM echocardiography with reasonable accuracy.

The utility of newly derived Doppler echocardiographic variables in the diagnosis and management of patients with heart failure

Doppler echocardiography, because of its noninvasive nature, is an ideal tool to evaluate patients with heart failure (HF), offering the potential to improve early identification and management of these patients. Although traditional Doppler indices have allowed characterization of diastolic filling abnormalities associated with various HF states, important limitations are recognized. More refined Doppler techniques such as analysis of color M-mode flow propagation velocity, tissue Doppler imaging, and strain parameters can add to the ability of the noninvasive laboratory to improve the identification and management of this group of patients. These newer techniques as well as the traditional Doppler assessment of transmitral left ventricular inflow and pulmonary venous inflow velocities are reviewed as methods to improve the diagnosis and management of patients with HF.

Intraoperative assessment of diastolic function: utility of echocardiography

PURPOSE OF REVIEW

This review discusses the current and future applications of different echocardiographic modalities in evaluating diastolic function intraoperatively.

RECENT FINDINGS

Normal diastolic function is required for optimal cardiac performance. There is sufficient evidence to support the significant prevalence of preoperative diastolic dysfunction and its incidence following cardiac surgery, however controversy still exists regarding the impact of diastolic dysfunction on adverse outcomes. Echocardiography provides a relatively safe, practical and noninvasive means to evaluate perioperative diastolic function, however conventional measures may be limited by the impact of changes in heart rate, rhythm and loading conditions. Newer echocardiographic modalities are reportedly less sensitive to acute changes in loading conditions, and may therefore complement the use of conventional echocardiographic techniques in the perioperative period.

SUMMARY

The availability of effective technology for diagnosing the presence and progression of perioperative diastolic function should assist in the identification of high-risk cardiac surgical patients who may benefit from appropriate triaging and therapeutic intervention.