Introduction
Hypertrophic cardiomyopathy (HCM) is a common inherited cardiac condition
affecting 1 in 500 of the population with a largely genetic autosomal
dominant pattern of inheritance. Left ventricular outflow tract obstruction
(LVOTO) is the most common clinical feature occurring in up to two thirds of
patients with HCM leading to clinical symptoms and premature death.
Different management strategies exist for LVOTO including pharmacological
and invasive interventional techniques.
Objectives
The main aim of this thesis is to examine and evaluate current clinical
practices and outcomes using varying surgical techniques in the
management of LVOTO in HCM.
Methods
A systematic review of the literature and meta-analysis were performed in
accordance with the PRISMA statement. Individual observational studies
were also performed comprising of various surgical populations using a large
relational database of patients with HCM in a single specialist
cardiomyopathy clinic located in London, UK.
Results
Meta-analysis: Contemporary early (30 days) mortality following septal
myectomy were 1.4% (CI 0.8, 2.4) I2 9.0%, p = 0.36 and 0.7% (CI 0.3, 1.2)
I2 70.7%, p 1 New York Heart Association (NYHA) class. There
were 5 perioperative deaths and 20 late deaths (>30 days). 58.9% of patients
undergoing mitral valve replacement alone did not improve their NYHA class.
Long-term (>30 days) complications included atrial fibrillation (29.6%),
transient ischaemic attack/stroke (2.4%) and heart failure hospitalisation
(3.2%). There were 16 repeat surgical interventions at 3.0 years.
Conclusions
Septal myectomy is a safe procedure resulting in symptomatic improvement
in the majority of patients. Ongoing clinical follow-up, surveillance and
medical therapy is recommended after surgery.