Association between global longitudinal strain and myocardial fibrosis biomarkers in patients with end-stage chronic kidney disease

Introduction

Myocardial fibrosis represents a landmark characteristic of uremic cardiomyopathy, leading to a high burden of arrhythmias, diastolic dysfunction (DD) and ultimately heart failure in this population. Collagen-derived biomarkers (Procollagen type I carboxy-terminal propeptide (PICP), Procollagen type III N-terminal peptide (P3NP)) and Galectin-3 (Gal-3) are associated with the extent of myocardial fibrosis on myocardial biopsy. Global longitudinal strain (GLS) as assessed by two-dimensional speckle tracking echocardiography (2D-STE) has been shown to detect subclinical myocardial dysfunction in various populations. The correlation between GLS and the serum level of these biomarkers has not been studied so far.

Purpose

The aim of this study was to evaluate the association between the left ventricular GLS measured by 2D-STE and the serum level of three biomarkers (PICP, P3NP, Gal-3) known to be associated with the presence of myocardial fibrosis, in patients with end-stage renal disease (ESRD), not on dialysis.

Methods

We conducted a cross-sectional study that included 135 patients with an eGFR (CKD-EPI) <15 ml/min/1.73 m2, stable, asymptomatic, not on dialysis. We performed a complete transthoracic echocardiography with 2D-STE and determined serum levels of PICP, P3NP and Gal-3 by ELISA. Patients in atrial fibrillation, with a permanent pacemaker or with a poor acoustic window were excluded.

Results

The mean age was 59.2±15.5 (median 61 years), 44% of the patients were males, 33% were diabetic, 11% had a history of myocardial infarction and 14% were smokers. The average volumetric ejection fraction (EF) was 54.4±9.8% (median 55%), with only 6.3% of the patients having an EF <40%. The majority of the patients (86.6%) had at least grade I DD, with only 5.3% having a restrictive pattern (grade III DD). The mean GLS was −16.8% ± 0.1 (median −17%). The average serum levels of PICP, P3NP and Gal-3 were 440.2±139.6, 244.9±380.1 and 10.8±6.7, respectively. After regression analysis, GLS was correlated with PICP, P3NP and Gal-3 levels (p=0.005, r=0.88; p=0.001, r=0.75; and p=0.006, r=0.81 respectively). Additionally, GLS was inversely correlated with the severity of DD (p=0.0001, r=0.84). In multiple regression analysis of a model consisting of GLS, PICP, P3NP and Gal-3, the serum level of PICP counted for 34% of the variance of GLS (R2=0.559, p=0.002, F=32.39).

Conclusions

In conclusion, this study proves that although stable and asymptomatic, patients with ESRD have lower values of GLS, a high proportion of DD and higher values of PICP, P3NP and Gal-3, when compared with the general population, in spite of a normal EF. Our study is the first to demonstrate that these biomarkers correlated with GLS in patients with ESRD, suggesting that GLS could represent an important tool for estimating the amount of fibrosis and risk stratification in this population.

Funding Acknowledgement

Type of funding sources: None.

The impact of COVID-19 on right ventricular function in chronic kidney disease patients

Introduction

In chronic kidney disease (CKD) patients, the case fatality rate caused by the severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) is higher than in the general population [1]. In patients hospitalised with COVID 19, right heart dysfunction is present in 20% of the cases, associated with an increased risk of all-cause death [2].

Purpose

CARDIO-SCARS in CKD is a currently ongoing multi-center observational match controlled trial that aims to assess the cardiovascular (CV) risk in a CKD (stages 3 to 5), dialysis and kidney transplant population, following SARS-CoV-2 infection, by using clinical evaluation, various techniques and novel biomarkers (ClinicalTrials.gov Identifier NCT05125913). We hereby report the main baseline echocardiographic parameters that assess the right ventricular (RV) function.

Methods

We conducted a cross-sectional study that included 263 patients with CKD (dialysis, transplantation or eGFR <60 ml/min/1.73 m²). For assessing RV function, 5 parameters were measured: fractional area change (FAC, %), tricuspid annular plane systolic excursion (TAPSE, mm), tricuspid S' wave (S tric, cm/s), Tei index and right ventricular free wall longitudinal strain (RVFWLS, %). Patients in atrial fibrillation, with a permanent pacemaker or with a poor acoustic window were excluded.

Results

Our study included 263 patients with CKD, divided in two groups: 168 patients post COVID-19 (94 in dialysis, 38 post kidney transplantation and 36 with CKD) and 95 patients in the control group (57 in dialysis, 30 post kidney transplantation and 8 with CKD).The mean age was 57.3±15.4 years (median 60 years old), 55.2% of the patients were males, 24% were diabetic and 9.5% were smokers. The mean duration of dialysis in the COVID-19 group was 63.8 months vs. 62.6 months in the control group. In the COVID group, the echocardiography was performed at a mean distance of 2.2±2.1 months after testing positive for SARS-CoV-2.All the parameters of RV function were better in the control group (FAC (%): 43.6±11 vs. 41.3±11; TAPSE (mm): 23.2±6.9 vs. 21.4±4.9; S tric (cm/s): 13.4±3.4 vs. 13±3.1; Tei index: 0.5±0.2 vs. 0.6±0.2; RVFWLS (%): −20.1±3.8 vs. −18.6±5.1. After performing a two-sample t-Test, statistical significance was reached only for TAPSE, Tei index and RVFWLS (0.008, 0.0001 and 0.006, respectively).

Conclusions

Our study is the first to describe echocardiographic alterations post-COVID in a CKD population. All CKD patients had lower values of RV parameters than those reported in the general population. Still, the CKD COVID group had lower values than CKD control group, with the same magnitude as the changes reported in the general population [3,4]. The evolution of these parameters and their prognostic significance is of interest, regarding long-term CV sequelae of COVID-19.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Ministry of Research and Innovation, CNCS-UEFISCDI

P186 In search of lost time

Arrhythmogenic right ventricular dysplasia (ARVD) is one of the most difficult to diagnose and manage of the cardiomyopathies. Physical exercise can be a contributing factor and may accelerate the progression of the disease.

We present the case of a 49-year-old, a former professional football player, with a history of cardiac arrest in 2011 by ventricular tachycardia (VT) (normal coronary arteries). Between 2011 and 2019 the patient didn"t present for reevaluation and resumed endurance sports activity in spite of doctor recommendation. In 2019 he was directed to our clinic for a syncope followed by constrictive anterior chest pain and palpitations, the clinical expression of a VT with LBBB morphology and inferior axis, most likely originated in the RVOT, for which cardioversion was required. Upon admission, the patient was hemodynamically and respiratory stable, at sinus rhythm 60/min with left anterior hemiblock and negative T waves in V1-V2. Biologically, myocardial and hepatic cytolysis enzymes were within normal limits, with mild hypokalemia. Echocardiography showed significant dilatation of RV and RVOT with RV dysfunction (TAPSE 16 mm, FAC 20%, s" 8.6 cm/s). LV was nondilated, with normal systolic function and kinetic, but with trabeculation of the apex. To confirm the diagnosis of ARVD, cardiac MRI was performed and confirmed fat infiltration in the RV free wall with biventricular involvement. Given the high arrhythmic risk (two resuscitated VT episodes, syncope), a two-chamber ICD was implanted, without immediate post-procedural complications.

In the second postprocedural day, the patient suddenly installed important epigastric pain with thoracic irradiation. The ECG showed sensing and pacing malfunction and radioscopy showed evidence of ventricular probe displacement. The echocardiography confirmed the myocardial perforation. Emergency surgery by median thoracotomy was performed, with successful extraction of the electrode and myocardial suture. Postoperative progression was favorable under treatment with beta-blocker and amiodarone. A subcutaneous ICD will be implanted as soon as available.

In conclusion, this case is a very particular one. First of all, we’ve documented two distinct phases in the evolution of the ARVD (electrical phase – 2011 and structural phase - 2019). Moreover, by resuming endurance sports activity and in concordance with the literature data, we can only assume that the progression of the disease was accelerated and the arrhythmic risk was greater. Complications related to probe stability are common in this population, but myocardial perforation is a very rare and dangerous one. The therapeutic management of patients with ARVD has evolved over the years and continues to be an important challenge. To further improve risk stratification and treatment of patients, more information is needed on the natural history, long-term prognosis, and risk assessment.

Abstract P186 Figure. Echocardiografic and MRI aspect