Energetic performance analysis of staged palliative surgery in tricuspid atresia using vector flow mapping

Vector flow mapping: A review from theory to practice

BACKGROUND

The interest in intra-cardiac blood flow analysis is rapidly growing, and it has encouraged the development of different non-invasive imaging techniques. Among these, Vector Flow Mapping (VFM), combing Color-Doppler imaging and speckle tracking data, seems to be a promising approach, feasible in adult and children population.

AIM OF THE REVIEW

The aim of this review is to give a historical perspective on the development of VFM method and a summary of the current algorithms and parameters potentially evaluable. Then, we will present the current state-of-the-art of VFM with an overview of clinical studies and applications of this technique.

Quantitative Analysis of Left Ventricular Flow Dynamics in Latent Obstructive Hypertrophic Cardiomyopathy Using Vector Flow Mapping

OBJECTIVES

This study aimed to assess left ventricular (LV) energy loss (EL), circulation and vortex area using vector flow mapping (VFM) in patients with latent obstructive hyper-trophic cardiomyopathy (LOHCM) and nonobstructive hypertrophic cardiomyopathy (NOHCM).

METHODS

Fourteen LOHCM patients, 10 NOHCM patients, and 11 healthy individuals were evaluated by transthoracic echocardiography. An offline VFM workstation was used to analyze the LV blood flow patterns and fluid dynamics. The hemodynamic parameters, EL, circulation, and vortex area in 7 cardiac phases were calculated and analyzed.

RESULTS

Compared with controls and NOHCM patients, EL was significantly higher in -LOHCM patients during the rapid ejection phase, slow ejection (SE) phase, and isovolumetric relaxation phase (p < 0.05). LOHCM patients also showed increased circulation during SE compared to the other two groups (p < 0.05). The ability to discriminate between NOHCM and LOHCM was assessed by the area under the receiver-operating characteristic curve (AUC), and EL during SE was found to have the largest AUC (0.964); the best cutoff value was 6.34 J/m3/s, with a sensitivity of 100% and specificity of 80%.

CONCLUSIONS

The VFM technique can detect abnormal changes of LV EL and vortex characteristics in hypertrophic cardiomyopathy patients. Compared with controls and NOHCM patients, the LOHCM patients have worse systolic and diastolic functions.

Energetic performance index improvement after Glenn and Damus-Kaye-Stansel procedure using vector flow mapping analysis: a case report

Background

Echocardiography vector flow mapping can assess dynamic flow to treat congenital heart diseases. We evaluated intracardiac flow, energy loss, left ventricular output kinetic energy, and energetic performance index using vector flow mapping during Glenn and Damus-Kaye-Stansel procedures in order to assess the efficacy of the surgery.

Case presentation

A 9-month-old boy underwent Glenn and Damus-Kaye-Stansel procedures. The energy loss depends on the left ventricular preload; therefore, energy loss decreased after the Glenn procedure. After the Damus-Kaye-Stansel procedure, the kinetic energy would increase owing to the integrated systemic outflow; however, in our case, kinetic energy decreased, which was potentially explained by the fact that kinetic energy also depends on the left ventricular preload. After the Glenn and Damus-Kaye-Stansel procedures, we detected an improvement in energetic performance index, indicating that the cardiac workload improved as well.

Conclusion

We revealed the efficiency of the Glenn and Damus-Kaye-Stansel procedures using vector flow mapping.