P5262Subclinical myocardial abnormalities in systemic sclerosis-associated versus non-connective tissue disease pulmonary hypertension by CMR multiparametric mapping

Introduction

Scleroderma (SSc)-associated pulmonary arterial hypertension (PAH) has the worst prognosis of all PAH subtypes despite having relatively more favourable haemodynamic and cardiac functional profiles. Myocardial abnormalities in SSc have been demonstrated by cardiovascular magnetic resonance (CMR) multiparametric tissue mapping. However, myocardial tissue characterisation studies across distinct PAH subtypes including SSc are limited.

Purpose

We compared indices of tissue characterisation by CMR multiparametric mapping between patients with SSc with and without PAH, non-connective tissue disease pulmonary hypertension (non-CTD PH) and healthy volunteers.

Methods

One-hundred and thirty-six patients underwent a CMR study over a 30-month period: 104 patients with systemic sclerosis, of whom 39 had SSc-PAH and 65 had no PH; 32 patients with idiopathic PAH, chronic thromboembolic PH or portopulmonary PH (non-CTD PH group). Patients underwent comprehensive CMR tissue characterisation including quantification of native myocardial T1 (MOLLI), myocardial T2 and ECV from automatically generated tissue maps along with conventional late gadolinium enhancement (LGE) imaging. Twenty age-matched controls underwent the same CMR study protocol. Patients were assessed for PH by right heart catheterisation.

Results

Native myocardial T1 and myocardial T2 and myocardial ECV are significantly elevated in SSc-PAH versus non-CTD PH (all p<0.05, Figure 1) despite no differences in LV systolic function between these patient cohorts. Patients with SSc have similar degrees of elevated T1, T2 and ECV irrespective of the presence or absence of PAH, suggesting a diffuse myocardial process due to SSc itself. Both SSc sub-groups have significantly higher T1, T2 and ECV compared with controls (all p<0.05).

All patients with SSc were subdivided by the presence or absence of ventricular insertion point LGE. Even in the absence of LGE, T1, T2 and ECV were significantly higher in SSc patients versus controls (all p<0.001). However, the presence of focal insertional LGE in SSc was not associated with different burdens of interstitial disease, as defined by median ECV. This highlights the unique role of multiparametric tissue maps in assessing diffuse myocardial involvement beyond the identification of focal LGE.

Conclusion

Subclinical abnormalities of the myocardium can be detected by CMR multiparametric tissue mapping in patients with SSc. The higher native myocardial T1 and T2 along with the elevated ECV in SSc-PAH are likely to be accounted for by SSc involvement itself. Abnormalities of the myocardial architecture could be a potential contributory reason for the poorer outcomes in SSc-PAH versus non-CTD PH despite the more favourable haemodynamics and right heart function observed in the former patient sub-group. Further work should be directed at determining the prognostic capacity of these metrics in SSc-PAH.

Acknowledgement/Funding

British Heart Foundation, Action Pharmaceuticals Ltd

Prospective comparison of novel dark blood late gadolinium enhancement with conventional bright blood imaging for the detection of scar

BACKGROUND

Conventional bright blood late gadolinium enhancement (bright blood LGE) imaging is a routine cardiovascular magnetic resonance (CMR) technique offering excellent contrast between areas of LGE and normal myocardium. However, contrast between LGE and blood is frequently poor. Dark blood LGE (DB LGE) employs an inversion recovery T2 preparation to suppress the blood pool, thereby increasing the contrast between the endocardium and blood. The objective of this study is to compare the diagnostic utility of a novel DB phase sensitive inversion recovery (PSIR) LGE CMR sequence to standard bright blood PSIR LGE.

METHODS

One hundred seventy-two patients referred for clinical CMR were scanned. A full left ventricle short axis stack was performed using both techniques, varying which was performed first in a 1:1 ratio. Two experienced observers analyzed all bright blood LGE and DB LGE stacks, which were randomized and anonymized. A scoring system was devised to quantify the presence and extent of gadolinium enhancement and the confidence with which the diagnosis could be made.

RESULTS

A total of 2752 LV segments were analyzed. There was very good inter-observer correlation for quantifying LGE. DB LGE analysis found 41.5% more segments that exhibited hyperenhancement in comparison to bright blood LGE (248/2752 segments (9.0%) positive for LGE with bright blood; 351/2752 segments (12.8%) positive for LGE with DB; p < 0.05). DB LGE also allowed observers to be more confident when diagnosing LGE (bright blood LGE high confidence in 154/248 regions (62.1%); DB LGE in 275/324 (84.9%) regions (p < 0.05)). Eighteen patients with no bright blood LGE were found to have had DB LGE, 15 of whom had no known history of myocardial infarction.

CONCLUSIONS

DB LGE significantly increases LGE detection compared to standard bright blood LGE. It also increases observer confidence, particularly for subendocardial LGE, which may have important clinical implications.

Statins in Aortic Stenosis

Calcific aortic stenosis (AS) is the most common form of valvular heart disease in Europe and North America. It is a progressive disease with a prolonged period of asymptomatic latency which eventually leads to critical left ventricular outflow tract obstruction necessitating surgical replacement of the valve. Statins are lipid-lowering drugs with a robust evidence base demonstrating clinical benefit in atherosclerotic coronary artery disease. There has therefore been significant interest in the potential benefit of statins in AS. Initial animal, retrospective and non-randomized prospective studies suggested a beneficial effect of statins in AS. However, the outcomes of 3 major randomized controlled clinical trials consistently failed to demonstrate any significant benefit of lipid-lowering therapy on progression or clinical outcomes in AS. Consequently, statin therapy should not be recommended if the sole purpose is prevention of AS progression and there is no other indication for lipid-lowering therapy. However, recent data have suggested that lipoprotein(a) (Lp(a)) may play a previously unknown but critical role in the progression of AS. Lp(a) is not significantly modified by statin therapy and there is therefore significant emerging interest in targeted reduction of Lp(a) with novel therapeutic agents such as PCSK9 inhibitors and antisense oligonucleotides.

Serum albumin changes and multivariate dynamic risk modelling in chronic heart failure

BACKGROUND

We examined the prognostic utility of rate of change in serum albumin over time in chronic heart failure (CHF), as well as the utility of multivariate dynamic risk modelling.

METHODS AND RESULTS

The survival implication of ∆albumin was analysed in 232 systolic CHF patients and validated in 212 patients. A multivariate dynamic risk score predicated on the rate of change in 6 simple indices including albumin was calculated and related to mortality. In derivation patients, 50 (22%) deaths occurred over 13 months. Greater rates of decline in albumin related to higher mortality (HR 0.55, 95% CI 0.41-0.73, P<0.0001) independently, incrementally and more accurately than other covariates including baseline albumin. A rate of attenuation >0.4 g/dL/month optimally forecasted death and was associated with a 5-fold escalated risk of mortality (HR 5.13, 95% CI 2.92-9.00, P<0.0001). Similar results were seen in the validation cohort. On multivariate dynamic risk modelling, survival at 1-year worsened with higher scores-a score ≥ 3 was associated with a 12-fold greater risk of death than a score of 0, a 6-fold higher risk of death than a score of 1, and a 4-fold enhanced risk of mortality than a score of 2.

CONCLUSION

Attenuations in serum albumin over time relate to increased mortality in CHF, and a risk model predicated on the rate of change in 6 simple indices can identify patients at a 12-fold enhanced risk of death over the coming year.