Impact on clinical outcomes of right ventricular response to percutaneous correction of secondary mitral regurgitation

Funding Acknowledgements

Type of funding sources: None.

Background. Right ventricular function (RVF) is a strong determinant of prognosis in patients with reduced ejection fraction heart failure (HFrEF) and secondary mitral regurgitation (SMR). Percutaneous mitral valve repair (pMVR) can promote the recovery of RVF.

Purpose. We sought to characterize the RV response to pMVR in HFrEF with SMR and to assess the influence of improved RVF after pMVR in this specific setting of patients.

Methods. We included all the patients with HFrEF and SMR≥3+ successfully treated with pMVR between April 2012 and January 2020 in two tertiary care centers for HF. Improved RVF was defined as DRVFAC≥5% at early follow-up (median time 4 months). The primary endpoint was a composite of death/heart transplant (D/HT).  

Results. In total, 110 patients were included. Mean age was 67 ± 12 years, mean LVEF was 31 ± 8% and mean RVFAC was 31 ± 10%. DRVFAC≥5% occurred in 54 (49%) patients and was independent from the measures of left ventricle recovery. During a median follow-up of 36 months (IQR 19-52), 40 patients (36%) died or were transplanted.  After adjustment for other significant covariates, DRVFAC≥5% was significantly associated with lower risk of D/HT (HR 0.49, 95% CI 0.24 – 0.98 p < 0.042) along with M2+ at follow-up (HR 0.36; 95% CI 0.17-0.74 p 0.005).

Conclusions. In patients with HFrEF and SMR, the improvement of RVF is frequent after pMVR and is associated with better long-term survival free from HT.

Abstract Figure.

Using intravascular ultrasound with drug-eluting stents. What have we learned so far?

Drug-eluting stents (DES) promise to change the landscape of interventional cardiology, overcoming restenosis that is the major limitation of percutaneous coronary interventions. Intravascular ultrasound (IVUS) examination has been at the centre of our efforts to understand the mechanisms and define different treatment strategies during coronary interventions. IVUS interrogation and 3-dimensional IVUS measurements have been used to better define the mechanisms of benefit and potential drawbacks of DES. The findings of these studies are summarized in this article and the potential importance of IVUS in the era of DES is discussed. Evidence of neointimal hyperplasia (IH) suppression and assessment of any edge effect or vessel remodeling after implantation of DES has been evaluated by IVUS. The overall clinical importance of IVUS in the new era will depend on the amount and the clinical significance of any unsolved questions we will face and on its ability to provide answers to the evolving questions.

Role of inflammation in the pathogenesis of unstable coronary artery diseases

Inflammation has been shown to play a pivotal role in ischemic heart disease, in particular unstable angina. The instability that characterizes this syndrome is related to the waxing and waning of ischemic stimuli, especially thrombotic ones. Angiographically and autoptically the severity of the atherosclerotic background in unstable angina does not differ from that in chronic stable angina, but in the former mural thrombi are often found and coronary atherosclerotic plaques are characterized by an inflammatory infiltrate, mostly consisting of activated lymphocytes, macrophages and mast-cells. In addition to these local findings, systemic evidence also suggests the importance of the role of inflammation in unstable angina as platelets, neutrophils and monocytes are activated, and elevated levels of serum markers of inflammation, e.g. C-Reactive Protein, have been consistently found. CRP has been demonstrated to be a reliable marker of prognosis in coronary heart disease. The consequences of inflammation are a disruption in the dynamic balance between antithrombotic and prothrombotic activities, an altered extracellular matrix metabolism, hyper-reactivity of cells such as monocytes and smooth muscle cells, all important features of unstable angina. These findings have important prognostic implications, since markers of inflammation are associated to a worse prognosis, and may also have therapeutic implications in the near future.

In vitro hyperreactivity to lipopolysaccharide in patients with history of unstable angina is not associated with seropositivity for Cytomegalovirus, Helicobacter pylori and Chlamydia pneumoniae

BACKGROUND

Inflammation and possibly chronic infections are associated with acute coronary syndromes; however, the mechanisms responsible for this association are not yet fully elucidated. The aim of this study was to assess whether the hyperreactivity of the inflammatory system, that we have shown in unstable patients with persistently elevated C-reactive protein and with recurrence of symptoms, was associated with chronic infection.

METHODS

In 20 unstable angina patients seropositivity and antibody levels vs Cytomegalovirus, Helicobacter pylori and Chlamydia pneumoniae were measured and correlated with the interleukin-6 production in vivo in 1 ml of whole blood stimulated with 0.1 microgram lipopolysaccharide for 4 hours.

RESULTS

No positive correlation was found between antibody titer and interleukin-6 levels. No correlation was also found between seropositivity to Cytomegalovirus, Helicobacter pylori or Chlamydia pneumoniae and interleukin-6 levels.

CONCLUSIONS

Our study suggests that seropositivity for infective agents, including Chlamydia pneumoniae, does not affect the monocyte response to lipopolysaccharide and thus cannot account for the enhanced interleukin-6 production observed in unstable angina patients with raised levels of C-reactive protein and worse prognosis, and suggests the predominant role of the individual response to different stimuli.