Remote ischaemic conditioning: defining critical criteria for success-report from the 11th Hatter Cardiovascular Workshop

The Hatter Cardiovascular Institute biennial workshop, originally scheduled for April 2020 but postponed for 2 years due to the Covid pandemic, was organised to debate and discuss the future of Remote Ischaemic Conditioning (RIC). This evolved from the large multicentre CONDI-2-ERIC-PPCI outcome study which demonstrated no additional benefit when using RIC in the setting of ST-elevation myocardial infarction (STEMI). The workshop discussed how conditioning has led to a significant and fundamental understanding of the mechanisms preventing cell death following ischaemia and reperfusion, and the key target cyto-protective pathways recruited by protective interventions, such as RIC. However, the obvious need to translate this protection to the clinical setting has not materialised largely due to the disconnect between preclinical and clinical studies. Discussion points included how to adapt preclinical animal studies to mirror the patient presenting with an acute myocardial infarction, as well as how to refine patient selection in clinical studies to account for co-morbidities and ongoing therapy. These latter scenarios can modify cytoprotective signalling and need to be taken into account to allow for a more robust outcome when powered appropriately. The workshop also discussed the potential for RIC in other disease settings including ischaemic stroke, cardio-oncology and COVID-19. The workshop, therefore, put forward specific classifications which could help identify so-called responders vs. non-responders in both the preclinical and clinical settings.

The utility of the 1994 versus the revised 2010 arrhythmogenic right ventricular cardiomyopathy (ARVC) task force diagnostic criteria for identifying mutation-positive probands with ARVC

Background

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiac disorder characterised by structural and functional abnormalities of the right ventricle with or without left ventricular involvement. In 1994, Task Force criteria (TFC) were proposed for the diagnosis of ARVC and were found to be highly specific but lacked sensitivity. In 2010, revised TFC were proposed to increase sensitivity and facilitate diagnosis in those with subtle phenotypes.

Purpose

To compare the utility of the 1994 vs the 2010 TFC for the diagnosis of mutation-positive probands with ARVC in the IMHOTEP (The African Cardiomyopathy and Myocarditis Registry Program) study.

Method

162 participants with the suspicion of ARVC were referred between May 2003 and May 2018. After the exclusion of 12 participants lacking sufficient clinical data, 150 cases were reviewed and classified using both 1994 and 2010 TFC by a diagnostic panel in an hospital.

Results

82 participants were found to have an alternative diagnosis or insufficient criteria and were excluded. 68 participants were diagnosed with ARVC by the diagnostic panel and included; 14/68 participants with ARVC were found to be mutation-positive. Mutation-positive probands presented at a significantly younger age compared to the mutation-negative group (29±14 years vs 39±13 years, p=0.009), suggesting an earlier onset of ARVC. Common reasons for presentation in the mutation-positive cohort included palpitations (79%) and presyncope (64%), with twice the number of participants presenting with sustained ventricular tachycardia compared to mutation-negative participants (79% vs 47%, p=0.036). The diagnostic yield of the 2010 vs 1994 TFC in participants with ARVC (n=68) revealed more participants with a definite diagnosis (77% vs 69%, p=0.267). A 67% change in diagnosis from 1994 borderline to 2010 definite was observed. Mutation-positive participants had a higher yield for definite ARVC compared to mutation-negative participants (100% vs 86%). When comparing the mean number of task force (TF) major and minor criteria according to mutation status, we found a significant difference in the mean number of 2010 TF major criteria between mutation-positive and mutation-negative groups, even with the exclusion of gene mutation as a criterion (2.50±0.86 vs 1.74±0.85, p=0.005). We assessed each diagnostic modality's contribution to the 2010 TF major criteria in mutation-positive definite participants and found cardiac magnetic resonance contribution statistically significant, p=0.021.

Conclusion

Mutation-positive ARVC probands were found to be younger, more likely to present with sustained VT, and fulfilled a significantly higher number of 2010 TF major criteria than mutation-negative probands. The evolution in classification between the 2010 and 1994 TFC suggests that reclassifying participants recruited in traditional ARVC registries according to updated criteria is worthwhile.

Funding Acknowledgement

Type of funding source: None