Ventricular-arterial Coupling of the Heart Among Patients With Mitral Stenosis Undergoing Percutaneous Trans-luminal Mitral Commissurotomy. Cardiac Magnetic Resonance Study

Ventricular-arterial Coupling of the Heart Among Patients With Mitral Stenosis Undergoing Percutaneous Trans-luminal Mitral Commissurotomy. Cardiac Magnetic Resonance Study

Although the incidence of rheumatic fever and its complications has declined in developed countries, the disease remains a major health problem in many developing countries. It is estimated that up to 30 million school-age children and young adults worldwide suffer from chronic rheumatic heart disease, and almost a third of them suffer from mitral valve stenosis (MS).

Various treatments are currently available to patients, including medical, surgical, and percutaneous mitral commissurotomy (PTMC), depending on the severity of symptoms, the type and severity of mitral stenosis, and the morphology of the mitral valve.

Successfully performed PTMC increases the optimal mitral valve area and is unlikely to result in significant mitral valve regurgitation. PTMC candidates are selected according to the latest European society of cardiology (ESC) guidelines for the treatment of mitral stenosis based on echocardiographic examination of the mitral valve and its dimensions. The Wilkins score, determined using ultrasound, is an important tool for patient selection.

CMR provides tomographic assessment of the heart with high spatial resolution and enables accurate assessment of ventricular volume, identification of segmental kinetic abnormalities, and detection of tissue changes such as fibrosis, edema, or fatty substitution.

Patients with severe mitral stenosis who underwent percutaneous mitral commissurotomy (PTMC) showed significant changes in right ventricular (RV) function. One study assessed the pre and post changes in RV function after PTMC and found significant improvements in RV parameters such as RV systolic pressure, RV outlet FS, RV TEi index, RV wall thickness, and pulmonary artery systolic pressure.

Successful balloon mitral valvuloplasty (BMV) in patients with rheumatic mitral stenosis (MS) is associated with improvement in left ventricular (LV) function and remodeling. A study using cardiac magnetic resonance imaging (CMR) found that BMV led to an increase in LV peak systolic global longitudinal strain (GLS) and global circumferential strain (GCS) at 6 months, with further improvement at 1 year.

Ventriculo-arterial coupling (VAC) plays an important role in the physiology of cardiac and aortic mechanics as well as in the pathophysiology of heart disease. VAC assessment has independent diagnostic and prognostic value and can be used to improve risk stratification and monitor therapeutic interventions. Traditionally, VAC is assessed by noninvasive measurement of the end-systolic elasticity ratio of arteries (Ea) and ventricles (Ees). Therefore, measuring any component of this ratio or new, more sensitive myocardial markers (e.g.B. global longitudinal strain) and arterial function (e.g. pulse wave velocity) can better characterize the VAC. In valvular heart disease, systemic arterial compliance and valve-arterial impedance have established diagnostic and prognostic value and can monitor the effects of valve replacement on vascular and cardiac function. Treatment to improve VAC by improving one of its components may delay the onset of heart failure and potentially improve the prognosis of heart failure.

According to Ozdogru I et al, A study of patients with severe mitral stenosis undergoing percutaneous balloon valvuloplasty and healthy subjects, demonstrated that mitral stenosis induced an increase in arterial stiffness that was improved after percutaneous balloon valvuloplasty.

Diastolic dysfunction has emerged as an important predictor of adverse outcomes in multiple forms of congenital heart disease.

A recently derived CMR prognostic tool, the left atrioventricular coupling index (LACI), has been evaluated as part of the Multi-Ethnic Study of Atherosclerosis (MESA). LACI is defined as the ratio between LA end-diastolic volume and LV end diastolic volume. It was created to determine whether the close physiological relationship between the LA and LV could serve as a primary prevention tool in the early detection of cardiovascular disease. LACI has been shown to serve as a strong predictor for the incidence of heart failure, atrial fibrillation, cardiovascular disease, and coronary heart disease death in healthy adult populations. A novel right atrioventricular coupling index can potentially help with risk stratification, novel parameter, termed the Right Atrioventricular Coupling Index (RACI), and was defined as the ratio of RA end-diastolic volume to right ventricle (RV) end-diastolic volume.

According to our knowledge there was no specific study was done using cardiac magnetic resonance imaging (CMR) for assessment of Ventricular-arterial coupling pre and post PTMC

Inclusion Criteria:

• Subjects with severe MS eligible for PTMC according to the recent ESC Guidelines for the management of valvular heart disease 2021

Exclusion Criteria:

1. Patient with contraindication to CMR (e.g. due to pacemakers, implantable cardioverter defibrillators, claustrophobia, .. etc)
2. Patients with associated coronary artery disease.
3. Patients with other significant valvular heart disease including organic tricuspid valve disease
4. Patients with any type of cardiomyopathy
5. Patients with renal impairment