Fate of preoperative moderate mitral regurgitation following left ventricular assist device implantation

Preoperative Echocardiographic Assessment in Elective Surgery Patients: A Cross-Sectional Study From Duhok, Iraqi Kurdistan

Background and aim Echocardiography plays a pivotal role in the preoperative risk assessment of patients undergoing various surgical procedures. Therefore, we conducted this study to detect various cardiac abnormalities through a preoperative echocardiographic study for cases undergoing elective surgeries in Duhok, Iraqi Kurdistan. Methods This cross-sectional study assessed echocardiographic findings in preoperative patients at Azadi Teaching Hospital, Duhok, Kurdistan Region of Iraq, from 2023 to 2024. The study encompasses 468 adult patients. We gathered clinicodemographic characteristics, indications of referral to a preoperative echo study, and the echocardiographic findings, particularly regional wall motion abnormalities, valvular heart diseases, and heart failure (systolic or diastolic/left ventricular hypertrophy). Results In a cohort of 468 patients, 205 (43.80%) were aged 35-54 years, and 269 (57.48%) were female. Most patients (366; 78.21%) resided in Duhok. Nearly only half of the cases 219 (46.79%) had clear preoperative echostudy indications. A total of 289 (61.74%) had no remarkable echocardiographic findings. Diastolic heart failure was most prevalent at 65 (13.89%). Older cases had more prevalent echo findings in terms of valve dysfunctions and heart failure. Notable associations were found between echocardiographic abnormalities and surgical types, particularly higher regional wall motion abnormalities in genito-urinary system operations (4; 8.16%) and valvular heart disease in orthopedic surgeries (13; 15.85%). Conclusions Echocardiographic abnormalities were remarkably observed in patients aged 65 and older. Many cases had no clear indications for preoperative echo study and hence unremarkable echo findings. More scrutiny is indicated during referral, and focusing on older adults' preoperative cardiac screening is recommended.

The role of innovative modeling and imaging techniques in improving outcomes in patients with LVAD

Heart failure remains a significant cause of mortality in the United States and around the world. While organ transplantation is acknowledged as the gold standard treatment for end stage heart failure, supply is limited, and many patients are treated with left ventricular assist devices (LVADs). LVADs extend and improve patients' lives, but they are not without their own complications, particularly the hemocompatibility related adverse events (HRAE) including stroke, bleeding and pump thrombosis. Mainstream imaging techniques currently in use to assess appropriate device function and troubleshoot complications, such as echocardiography and cardiac computed tomography, provide some insight but do not provide a holistic understanding of pump induced flow alterations that leads to HRAEs. In contrast, there are technologies restricted to the benchtop-such as computational fluid dynamics and mock circulatory loops paired with methods like particle image velocimetry-that can assess flow metrics but have not been optimized for clinical care. In this review, we outline the potential role and current limitations of converging available technologies to produce novel imaging techniques, and the potential utility in evaluating hemodynamic flow to determine whether LVAD patients may be at higher risk of HRAEs. This addition to diagnostic and monitoring capabilities could improve prevention and treatment of LVAD-induced complications in heart failure patients.

Prognostic value of mitral regurgitation in patients undergoing left ventricular assist device deployment: A systematic review and meta-analysis

BACKGROUND

Left ventricular assist devices (LVADs) represent an important therapeutic option for patients progressing to end-stage heart failure. LVAD has previously been shown to have a promising role in improving mitral regurgitation (MR). Nevertheless, the prognostic value of preoperative uncorrected MR in this population remains unclear.

METHODS

A systematic database search with meta-analysis was conducted of comparative original articles of patients with preoperative mild MR (Grade 0-I) versus moderate-severe MR (Grade II-III) undergoing LVAD implantation, in EMBASE, MEDLINE, Cochrane database, and Google Scholar, from inception to June 2022. Primary outcomes were overall and operative mortality. Secondary outcomes were neurological dysfunction, gastrointestinal bleeding, right heart failure, LVAD thrombosis, and driveline infection.

RESULTS

Our search yielded 2228 relevant studies. A total of 19 studies met the inclusion criteria with a total of 11 873 patients. LVAD caused a statistically significant decrease of 35.9% in the number of patients with moderate-severe MR (grade II-III) postoperatively. No significant difference was observed in terms of overall mortality, operative mortality, GI bleeding, LVAD thrombosis, and driveline infection rates between mild and moderate-severe MR. An increased rate of right heart failure was seen among patients with moderate-severe MR, while lower rates of neurological events were also observed.

CONCLUSION

LVAD improves the haemodynamics of the left ventricle, to promote resolution of MR. Nevertheless, the severity of preoperative mitral regurgitation in patients undergoing LVAD deployment does not seem to affect mortality.

Role of the mitral valve in left ventricular assist device pathophysiology

Functional mitral regurgitation (MR) in the setting of heart failure results from progressive dilatation of the left ventricle (LV) and mitral annulus. This leads to leaflet tethering with posterior displacement. Contrary to common assumptions, MR often does not resolve with LVAD decompression of the LV alone. The negative impact of significant (moderate-severe) mitral regurgitation in the LVAD setting is becoming better recognized in terms of its harmful effect on right heart function, pulmonary vascular resistance and hospital readmissions. However, controversies remain regarding the threshold for intervention and management. At present, there are no consensus indications for the repair of significant mitral regurgitation at the time of LVAD implantation due to the conflicting data regarding potential adverse effects of MR on clinical outcomes. In this review, we summarize the current understanding of MR pathophysiology in patients supported with LVAD and potential future management strategies.