Management and clinical outcomes of patients with homozygous familial hypercholesteremia in Saudi Arabia

Modern approaches to the management of homozygous familial hypercholesterolemia in the Middle East and North Africa

Homozygous familial hypercholesterolaemia (HoFH) is a severe form of FH in which inheritance of two defective or null mutations in genes associated with metabolism of low-density lipoprotein cholesterol (LDL-C) results in extremely high LDL-C, premature atherosclerotic cardiovascular disease (ASCVD) and mortality. Treatment of HoFH comprises a multi-modal approach of statins, ezetimibe, lipoprotein apheresis; and inhibitors of proprotein convertase subtilisin/kexin type, angiopoietin-like protein 3 (ANGPTL3) and microsomal triglyceride transfer protein. These treatments are generally costly, and patients also often require treatment for ASCVD consequent to HoFH. Therefore, in the interests of both economics and preservation of life, disease prevention via genetic screening and counselling is rapidly becoming a key element in the overall management of HoFH. Guidelines are available to assist diagnosis and treatment of HoFH; however, while advancements have been made in the management of the disease, there has been little systematic attention paid to prevention. Additionally, the Middle East/North Africa (MENA) region has a higher prevalence of HoFH than most other regions - chiefly due to consanguinity. This has led to the establishment of regional lipid clinics and awareness programs that have thrown education and awareness of HoFH into sharp focus. Incorporation of principles of prevention, education, awareness, and data from real-world use of existing therapeutics will significantly enhance the effectiveness of future guidelines for the management of HoFH, particularly in the MENA region.

The Effect of PCSK9 Inhibitors on LDL-C Target Achievement in Patients with Homozygous Familial Hypercholesterolemia: A Retrospective Cohort Analysis

INTRODUCTION

Achieving target low-density lipoprotein-cholesterol (LDL-C) levels remains challenging when treating homozygous familial hypercholesterolemia (HoFH). Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) are prescribed in addition to statins and ezetimibe, but patients' response varies and depends on residual low-density lipoprotein receptor (LDLR) function.

METHODS

A multicenter, retrospective observational analysis evaluated LDL-C target achievement in response to PCSK9i treatment in 28 patients with HoFH from the Middle East/North Africa region. Effect of genotype was investigated. Demographic and clinical information was retrospectively obtained from medical records. Patient response to PCSK9i treatment was assessed by calculating percentage changes in lipid levels from pre-PCSK9i treatment baseline to most recent follow-up visit where patients were recorded as receiving PCSK9i on top of standard of care lipid-lowering therapies (LLTs; i.e., statins/ezetimibe) and assessing European Atherosclerosis Society (EAS) target achievement up to January 31, 2022. Lowest LDL-C level while receiving PCSK9i was identified.

RESULTS

The cohort (n = 28) had a mean age (standard deviation; SD) of 22.8 (9.8) years (n = 28) and was 51% female (n = 27). Baseline LDL-C data were available in 24/28 (85.7%) patients (mean [SD] 14.0 [3.0] mmol/L). Median (interquartile range) duration of PCSK9i treatment was 12.0 months (4.0-19.1) months and mean (SD) % change in LDL-C after PCSK9i treatment was - 8.6% (12.1). LDL-C reduction from baseline was below 15% in 17/24 patients (70.8%). In the full cohort, mean (SD) minimum LDL-C during PCSK9i treatment was 11.9 (2.8; n = 28) mmol/L. No patient achieved EAS target LDL-C while receiving PCSK9i; genotype analysis suggested LDLR-null/null patients were most refractory to PCSK9i.

CONCLUSION

Response to PCSK9i was minimal in this cohort of patients with HoFH. No patients achieved EAS LDL-C targets, and most failed to reach the EAS-recommended 15% LDL-C reduction for PCSK9i therapy continuation. These results suggest additional LLTs are necessary to achieve LDL-C targets in HoFH.

The Ross Procedure: Imaging, Outcomes and Future Directions in Aortic Valve Replacement

The Ross procedure is gaining recognition as a significant option for aortic valve replacement (AVR), and is particularly beneficial in specific patient groups. Although categorized as a class IIb recommendation in the 2020 American College of Cardiology (ACC)/American Heart Association (AHA), and the European Society of Cardiology (ESC) management guidelines on valvular heart disease, recent studies bolster its credibility. Research, including a propensity-matched study, underlines the Ross procedure's association with enhanced long-term survival and reduced adverse valve-related events compared to other AVR types. This positions the Ross procedure as a primary option for AVR in young and middle-aged adults within specialized centers, and potentially the only choice for children and infants requiring AVR. This review meticulously examines the Ross procedure, covering historical perspectives, surgical techniques, imaging, and outcomes, including hemodynamic performance and quality of life, especially focusing on pediatric and young adult patients. It explores contemporary techniques and innovations like minimally invasive approaches and tissue engineering, underscoring ongoing research and future directions. A summarization of comparative studies and meta-analyses reiterates the Ross procedure's superior long-term outcomes, valve durability, and preservation of the left ventricular function, accentuating the crucial role of patient selection and risk stratification, and pinpointing areas for future research.

Transplantation of heterozygous familial hypercholesterolemia living donor liver resulting in early myocardial infarction: a possible dangerous link

Living donor liver transplantation (LDLT) is a lifesaving procedure that is often curative for several liver diseases. Familial hypercholesterolemia (FH) is a metabolic disease that results from an autosomal dominant mutation in the low-density lipoprotein receptor; yet, young patients with FH can live years without detection. Herein, we report a case of a patient who developed early myocardial infarction (MI) after having a transplant from a donor with undetected heterozygous FH. This was a 67-year-old female with non-alcoholic steatohepatitis-related liver cirrhosis, free from coronary artery disease, who underwent LDLT from her daughter, a 45-year-old female with no past medical history. One year post-transplant, she presented with an acute MI with a large atherosclerotic burden. Genetic analysis confirmed heterozygous FH in the donor but not in the recipient. This case emphasizes the importance of incorporating a thorough clinical history and lipid profile into pre-transplant testing for both the recipient and donor, as well as aggressive lipid-lowering therapy post-transplantation to avoid cardiovascular complications.