Recurrent immunosuppressive-responsive myocarditis in a patient with desmoplakin cardiomyopathy: a case report

Background

Desmoplakin (DSP) cardiomyopathy is a rare genetic condition characterized by repeated inflammatory myocardial injury and is associated with ventricular arrhythmia and sudden cardiac death. Diagnosis is challenging and requires a combination of genetic testing and advanced imaging techniques.

Case summary

We present the case of a 38-year-old woman with recurrent episodes of subclinical myocarditis. Investigation using cardiac magnetic resonance imaging (cMRI) and genetic testing revealed a diagnosis of DSP cardiomyopathy. Her disease was initially responsive to corticosteroid therapy but quickly relapsed when treatment was tapered. Management of her condition required significant immunosuppression and the subsequent insertion of an implantable cardiac defibrillator due to her risk of sudden cardiac death.

Discussion

Cardiac MRI and genetic testing are key diagnostic techniques in the assessment of patients with recurrent myocarditis and cardiomyopathy. The management of cardiomyopathies with an inflammatory component is not completely understood; however, there is likely a key role for immune suppression therapies. Furthermore, there are several cardiomyopathy genetic variants including DSP which require careful risk stratification due to an increased risk of sudden cardiac death.

Factors associated with functional arteriovenous fistula at hemodialysis start and arteriovenous fistula non-use in a single-center cohort

BACKGROUND

The gold standard of commencing hemodialysis with a functional arteriovenous fistula (AVF) is challenging. We aim to review factors associated with functional AVF at hemodialysis start at a tertiary hospital.

METHODS

We retrospectively reviewed incident hemodialysis patients or who had AVF creation at a single tertiary hospital from 2011 to 2016. Data was extracted for patient comorbidities, duration from referral to AVF creation and hemodialysis start, estimated glomerular filtration rate (eGFR) at surgical referral, referring nephrologist, events accelerating eGFR decline, and revisions for "failing to mature" AVF to assess factors associated with non-functioning AVF or late AVF creation, using multinomial logistic regression.

RESULTS

Two hundred two patients received hemodialysis and 51 had AVF creation but did not dialyze (AVF futility rate 20%). Of these, 133 (66%) commenced hemodialysis with a central venous catheter (CVC) and 69 (34%) with an AVF. Patients with functional AVFs at hemodialysis start were referred earlier than those with non-functional AVFs (median 256 vs 66 days before hemodialysis start, p = 0.001). Age, sex, eGFR at surgical referral, and comorbidities were not predictive of patients with functional AVFs. Events accelerating eGFR decline were associated with an increased incidence of CVC at hemodialysis start (risk ratio (RR) 4.21, 95% confidence interval (CI) 1.96-9.03, p < 0.0001). Referring nephrologists external to our renal unit may be associated with non-functional AVF at hemodialysis start (RR 6.60, 95% CI 1.74-25.13, p = 0.006).

CONCLUSIONS

We found that functional AVFs required referral a median of 256 days prior to hemodialysis start and events accelerating eGFR decline increase the incidence of CVC at hemodialysis start. Age, sex, eGFR at surgical referral, and comorbidities did not inform the likelihood of timely AVF creation and evaluation of further predictive pre-dialysis factors is necessary to identify patients requiring early AVF creation whilst minimizing the cost of unnecessary procedures.