Percutaneous Mitral Valve Repair in Mitral Regurgitation Reduces Cell-Free Hemoglobin and Improves Endothelial Function

Mechanical atherothrombectomy improves endothelial function through plaque burden reduction in PAD

Summary: Background: Endothelial dysfunction defines outcomes and serves as a surrogate parameter for the progression of cardiovascular disease. For symptomatic peripheral artery disease (PAD) endovascular treatment is the primary revascularization strategy, which affects endothelial function. Interventional mechanical atherothrombectomy (MATH) provides advantages when treating complex atherosclerotic and thrombotic lesions. We now aimed to determine the impact and mechanisms of MATH on endothelial function. Patients and methods: Endothelial function was determined using flow-mediated dilation (FMD) before and after lower limb intervention with a six-month follow-up in the target and control vessel in 15 PAD MATH+DCB treated patients and compared to 15 non-Math controls. In a further cohort of 20 patients the impact of MATH and DCB on vascular structure and virtual histology was assessed through intravascular ultrasound (IVUS) and compared to DCB treatment alone. Results: Improved endothelial function after 6 months was observed in both groups for the target and nontarget vessel. When comparing the changes from baseline endothelial function, treatment with MATH+DCB was superior to DCB treatment in the target vessel. IVUS revealed a greater improvement in luminal area and plaque burden reduction after MATH treatment. Virtual histology disclosed MATH-associated changes in plaque composition evidenced by alterations in fibrous volume and reductions in superficial calcium. Conclusions: We demonstrate an improved endothelial function after MATH treatment as compared to DCB treatment. The improved vessel function is evidenced by MATH-related plaque burden reduction, improved luminal gain and a decrease in superficial calcification. Clinicaltrials.gov: NCT04092972.

The impact of percutaneous peripheral interventions on endothelial function

Background: Treatment of symptomatic peripheral artery disease (PAD) through endovascular interventions is the primary revascularization strategy. Interventions restore perfusion but may cause severe injury to the vascular endothelium, which regulates vascular tone. Endothelial dysfunction is involved in the progression of cardiovascular disease, with higher incidences of vascular events. We aimed to determine the impact of percutaneous interventions on change in endothelial function. Patients and methods: Endothelial function was determined using flow-mediated dilation (FMD) before, the day after lower limb intervention with paclitaxel-coated balloons or stent guided interventions and after a six-month follow-up in the target limb, control limb and the systemic circulation in 42 PAD patients aged 70.2±9 years and 66% men. Additionally, macro- and microvascular function were assessed. Results: In PAD patients aged 70.2±9 years and 66% men, we observed an immediate enhancement of macro-, microvascular and endothelial function after endovascular treatment (FMD of superficial femoral artery (SFA) 3.7±0.2% to 4.1±0.1%, n=42, p=0.02), a sustained long-term improvement after 6-months (FMD SFA 3.7±0.2% to 4.2±0.1%, n=42, p=0.01), and moreover an improved systemic endothelial function (FMD brachial artery 4.3±0.1% to 4.7±0.2, n=42, p=0.01) following peripheral interventions. Subgroup analysis however revealed that following paclitaxel-based percutaneous intervention, the paclitaxel dosage applied was inversely related to the chronic improvement in local endothelial function (r=-0.6, n=22, p=0.005) without evidence for systemic effects (r=-0.25, p=0.27). Conclusions: We demonstrate an improved local and systemic endothelial function after treatment of atherosclerotic peripheral disease with a distinguished response after endovascular intervention with higher dosage of applied paclitaxel restraining the benefits. Further studies have to determine the optimal interventional strategy with respect to different treatment modalities to maintain vessel functions.

Rapid and automated risk stratification by determination of the aortic stiffness in healthy subjects and subjects with cardiovascular disease

Background

Aortic stiffness is an independent predictor of cardiovascular morbidity and mortality; thus, simple, rapid and preferably automated techniques are indispensable for pursuing a global risk stratification approach. We present an oscillometric technique for determination of the carotid-femoral pulse wave velocity (cfPWV), including the diagnostic accuracy, sensitivity and specificity, with emphasis on the training curve and procedural duration.

Methods

In a single-centre crossover study, we evaluated subjects free of known cardiovascular disease (CVD), subjects with CVD and a subgroup of subjects with peripheral artery disease (PAD) in terms of ankle-brachial index (ABI) and PWV measurements determined by oscillometry compared to tonometry. Pearson’s correlation analysis was used to assess the relationship of the PWV measurements determined by both methods. Moreover, the time and cost of the examinations were compared.

Results

A total of 176 study subjects underwent assessments to obtain oscillometric and tonometric PWV measurements. The CVD-free subjects (n = 59) were younger (60.4±15.6 vs. 67.5±12.9 years, p = 0.003) than the subjects with CVD (n = 117). The PWV measurements showed significant correlations in CVD-free subjects (r = 0.797, p<0.001), in subjects with CVD (r = 0.817, p<0.001) and in the subgroup of subjects with PAD (r = 0.807, p<0.001). The examination duration was shorter for the oscillometric method than the tonometric method (4.4±0.5 vs. 9.2±0.8 min, p<0.001).

Conclusion

Using a simple and rapid automated oscillometric method, we achieved good diagnostic accuracy for the determination of aortic stiffness through the PWV in both subjects with and without CVD. This method might be helpful in daily practice in terms of saving time and reducing procedural complexity for screening for cardiovascular morbidities and vascular damage in cases of atherosclerosis.

Interrelationship Between Kidney Function and Percutaneous Mitral Valve Interventions: A Comprehensive Review

Percutaneous mitral valve repair is emerging as a reasonable alternative especially in those with an unfavorable surgical risk profile in the repair of mitral regurgitation. At this time, our understanding of the effects of underlying renal dysfunction on outcomes with percutaneous mitral valve repair and the effects of this procedure itself on renal function is evolving, as more data emerges in this field. The current evidence suggests that the correction of mitral regurgitation via percutaneous mitral valve repair is associated with some degree of improvement in cardiac function, hemodynamics and renal function. The improvement in renal function was more significant for those with greater renal dysfunction at baseline. The presence of Chronic Kidney Disease (CKD) in turn has been associated with poor long-term outcomes including increased mortality and hospitalization among patients who undergo percutaneous mitral valve repair. This was true regardless of the degree of improvement in GFR post repair advanced CKD. The adverse impact of CKD on long-term outcomes was consistent across all studies and was more prominent in those with GFR<30 mL/min/1.73 m². It is clear that from these contrasting evidences of improved renal function post mitral valve repair but poor long-term outcomes including increased mortality in patients with CKD, that proper patient selection for percutaneous mitral valve repair is key. There is a need to have better-standardized criteria for patients who should qualify to have percutaneous mitral valve replacement with Mitraclip. In this new era of percutaneous mitral valve repair, much work needs to be done to optimize long-term patient outcomes.