Left atrial strain at CMR is a strong independent prognostic predictor in DCM, superior to LV-GLS, LVEF and LAVI, and incremental to LGE

Background

The left atrium (LA) is an early sensor of left ventricular (LV) dysfunction. LA size and new-onset atrial fibrillation (AF) are associated with an increased risk of mortality and heart failure (HF) progression in patients with dilated cardiomyopathy (DCM). Whether abnormal LA strain measured at cardiac magnetic resonance (CMR) – a new technology to study atrial function – may predict overall outcome in DCM – either or not leading to new onset AF – remains completely unknown.

Purpose

To determine the prognostic value of CMR derived LA strain in DCM patients.

Methods

A total of 488 DCM patients (age 54 [46–62] years, 61% male) undergoing CMR were prospectively enrolled in the Maastricht Cardiomyopathy Registry between 2004 and 2018. Outcome consisted of the combination of sudden or cardiac death, HF hospitalization or life-threatening arrhythmias. LA reservoir (passive LA filling), conduit (passive LV filling), and booster strain (active LV filling) were measured using feature tracking strain analysis of the 2- and 4-chamber long-axis cines (Figure 1). Given the non-linearity of continuous variables, cubic spline analysis was performed to dichotomize.

Results

Seventy out of 488 DCM patients (14%) reached the endpoint (follow-up 6 [4–9] years). Age, NYHA class ≥3, late gadolinium enhancement (LGE) presence, LV ejection fraction (EF), LA volume index (LAVI), LV global longitudinal strain (GLS), and LA reservoir and conduit strain were univariably associated with worse outcome (all p-values <0.02). LA conduit strain was superior to reservoir strain to predict outcome. LA conduit strain, NYHA class ≥3 and LGE remained associated in the multivariable model (Figure 2A), while age, NTproBNP, LVEF, LA ejection fraction, LAVI and LV-GLS did not. Adding LA conduit strain to NYHA class and LGE significantly improved the calibration, accuracy, and reclassification of the prediction model (p<0.05). In patients without known AF and sinus rhythm (n=425) during CMR, 10% developed new-onset AF (paroxysmal or persistent) at long-term. Higher age, male sex, NYHA class ≥3, higher LAVI and impaired booster strain were all univariably associated with new-onset AF. Age and impaired booster strain remained as independent predictors of new-onset AF in the multivariable analysis (Figure 2B).

Conclusions

LA conduit strain on CMR is a strong independent prognostic predictor in DCM, superior to LV-GLS, LVEF and LAVI, and incremental to LGE. In addition, LA booster strain is an independent predictor of new-onset AF.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Netherlands Cardiovascular Research Initiative, an initiative with support of the Dutch Heart Foundation

Age is the main determinant of COVID-19 related in-hospital mortality with minimal impact of pre-existing comorbidities, a retrospective cohort study

BACKGROUND

Age and comorbidities increase COVID-19 related in-hospital mortality risk, but the extent by which comorbidities mediate the impact of age remains unknown.

METHODS

In this multicenter retrospective cohort study with data from 45 Dutch hospitals, 4806 proven COVID-19 patients hospitalized in Dutch hospitals (between February and July 2020) from the CAPACITY-COVID registry were included (age 69[58-77]years, 64% men). The primary outcome was defined as a combination of in-hospital mortality or discharge with palliative care. Logistic regression analysis was performed to analyze the associations between sex, age, and comorbidities with the primary outcome. The effect of comorbidities on the relation of age with the primary outcome was evaluated using mediation analysis.

RESULTS

In-hospital COVID-19 related mortality occurred in 1108 (23%) patients, 836 (76%) were aged ≥70 years (70+). Both age 70+ and female sex were univariably associated with outcome (odds ratio [OR]4.68, 95%confidence interval [4.02-5.45], OR0.68[0.59-0.79], respectively;both p<  0.001). All comorbidities were univariably associated with outcome (p<0.001), and all but dyslipidemia remained significant after adjustment for age70+ and sex. The impact of comorbidities was attenuated after age-spline adjustment, only leaving female sex, diabetes mellitus (DM), chronic kidney disease (CKD), and chronic pulmonary obstructive disease (COPD) significantly associated (female OR0.65[0.55-0.75], DM OR1.47[1.26-1.72], CKD OR1.61[1.32-1.97], COPD OR1.30[1.07-1.59]). Pre-existing comorbidities in older patients negligibly (<6% in all comorbidities) mediated the association between higher age and outcome.

CONCLUSIONS

Age is the main determinant of COVID-19 related in-hospital mortality, with negligible mediation effect of pre-existing comorbidities.

TRIAL REGISTRATION

CAPACITY-COVID ( NCT04325412 ).

Diagnostic approach of myocarditis: strike the golden mean

Myocarditis is a challenging diagnosis due to the extreme diversity of clinical manifestations. The actual incidence of myocarditis is also difficult to determine as endomyocardial biopsy (EMB), the diagnostic gold standard, is used infrequently. Nevertheless, in up to 30 % of patients with biopsy-proven myocarditis, progression to dilated cardiomyopathy (DCM) can occur and is associated with a poor prognosis. Recent position statements of the European Society of Cardiology (ESC) and the American Heart Association vary widely with regard to indications for performing an EMB in these patients. This makes decision-making, in particular for general practitioners (GPs) and regional hospitals, difficult and unclear. Therefore, we will present a short summary of the ESC Working Group on Myocardial and Pericardial Diseases statement and our suggestions for GPs and regional hospitals for the diagnostic approach in patients with suspected myocarditis.