Ethnicity, consanguinity, and genetic architecture of hypertrophic cardiomyopathy

AIMS

Hypertrophic cardiomyopathy (HCM) is characterized by phenotypic heterogeneity that is partly explained by the diversity of genetic variants contributing to disease. Accurate interpretation of these variants constitutes a major challenge for diagnosis and implementing precision medicine, especially in understudied populations. The aim is to define the genetic architecture of HCM in North African cohorts with high consanguinity using ancestry-matched cases and controls.

METHODS AND RESULTS

Prospective Egyptian patients (n = 514) and controls (n = 400) underwent clinical phenotyping and genetic testing. Rare variants in 13 validated HCM genes were classified according to standard clinical guidelines and compared with a prospective HCM cohort of majority European ancestry (n = 684). A higher prevalence of homozygous variants was observed in Egyptian patients (4.1% vs. 0.1%, P = 2 × 10-7), with variants in the minor HCM genes MYL2, MYL3, and CSRP3 more likely to present in homozygosity than the major genes, suggesting these variants are less penetrant in heterozygosity. Biallelic variants in the recessive HCM gene TRIM63 were detected in 2.1% of patients (five-fold greater than European patients), highlighting the importance of recessive inheritance in consanguineous populations. Finally, rare variants in Egyptian HCM patients were less likely to be classified as (likely) pathogenic compared with Europeans (40.8% vs. 61.6%, P = 1.6 × 10-5) due to the underrepresentation of Middle Eastern populations in current reference resources. This proportion increased to 53.3% after incorporating methods that leverage new ancestry-matched controls presented here.

CONCLUSION

Studying consanguineous populations reveals novel insights with relevance to genetic testing and our understanding of the genetic architecture of HCM.

Drive line infection rate reduction by developing a fixation kit

Funding Acknowledgements

Type of funding sources: None.

Introduction

Continuous-flow left ventricular assist device (LVAD) therapy has become a standard therapy for patients suffering from end-stage heart failure. One of the serious adverse events during LVAD support is infection. Infections can trigger thromboembolic events, haemorrhagic cerebrovascular accidents , and are the second most common cause of death. Moreover, LVAD-related infection is the leading cause of re-admission and increases the cost of LVAD therapy considerably. Patients with an infection during LVAD support need a significantly prolonged hospital stay.

Background

Left ventricular assist device implantation is one of the operations that patients need special and distinctive health care, and therefore a specialized medical team has been appointed to examine these patients, but from the time the device is installed, these patients suffer from frequent infections at the drive line exit site, and therefore the responsible team faces a great challenge in combating this infection and reducing the infection rate and complications. One of the biggest problems is that we cannot find the exact type of dressing that is used to care for the exit, With the increase in the number of patients who have an infection in the drive line exit site, the team started to identify the reasons that lead to this, and it was found that failure to the fixation of the drive line is one of the biggest causes of infection, and patients reported that the movement of the drive line causes them severe pain and inflammation, which leads to many difficulties in their mobility and daily activities.

Aim

Reaching the best practice and reducing drive line infection rate by managing drive line fixation while increasing the number of the implanted devices.

Process: The LVAD nursing team started in collecting data related to the drive line infection and some modifications were implemented according to the available resources to be used in the drive line modified fixation technique:

Step 1: Our available adhesive dressings were used, and two small holes were made in the middle of it. Figure 1

Step 2: A small gauze strip was passed through the two holes to be fixed around the drive line. Figure 2

Step 3: Then a surgical blade used to make a whistling hole in the adhesive dressing to exit the drive line from it. Figure 3

Results

Based on:

Auditing charts and data collection it shows significant decrease in infection rates and re-admission related to drive line infection.

Recommendation

Develop new material for education

Videos in Arabic, Follow-up handbook and Posters.

Updating AHC staff with the latest driveline wound care protocol

Training sessions, Case study and Simulation lab.