Hypertrophic cardiomyopathy (HCM) developed as a monogenic inherited cardiac muscular disease with an incidence of about 0.2%. The clinical presentation of HCM is diverse and the pathophysiology is complex, yet therapeutic strategies are effective and available. It has transitioned from a rare and nearly uncurable disease to a common genetic disorder up to now. It is considered as an important cause of arrhythmic cardiac arrest, heart failure, and atrial fibrillation (with embolic stroke). Clinical diagnosis is primarily based on unexplained left ventricular hypertrophy as determined by echocardiography or cardiovascular magnetic resonance imaging (MRI).
Single coronary artery (SCA) is a rare congenital coronary artery developing abnormality with an incidence of 0.024–0.066% that only one coronary artery emerges from a coronary ostium, and supplies the entire heart. In 1979, Lipton et al. proposed a very useful classification of single coronary artery malformations based on a large number of clinical cases. The classification was further improved by Yamanaka and Hobbs in 1990, it was divided into different subtypes according to the origin and course of coronary artery. The first level of classification is divided into right type (R) and left type (L) according to the origin of the single coronary artery; the second level of classification is divided into type I, type II and type III according to the course of coronary branches. Type I: The artery runs along the anatomical route of the left coronary artery (LCA) or the right coronary artery (RCA). The CX provides the posterior descending artery, runs in the posterior atrioventricular groove, and also CX branches supply the right atrium and right ventricle; in the absence of LCA, a very large right coronary artery (RCA) is located in the posterior atrioventricular groove, and extends to the anterior base of the heart, where it forms an anterior descending artery (LAD). Type II: The other coronary artery originates proximal to the normally located one, passing through the base of the heart before reaching the normal part of the native coronary artery. Type III: single coronary artery originates from the right coronary sinus, while the left anterior descending (LAD) and left circumflex (LCX) branches originate from the common trunk, respectively. According to this classification, this patient belongs to the L-I type originating from the left coronary sinus.
In fact, HCM and coronary artery abnormalities are considered to be the leading causes of exercise-related cardiac arrest, especially in young adults. SCA can be an isolated congenital heart disease. However, when it coexists with certain other congenital anomalies, it is found much more frequently. In the published literature, congenital anomalies coexisting with SCA include coronary aneurysm , coronary arteriovenous fistula , ventricular septal defect, transposition of great vessels, patent foramen ovale , tetralogy of Fallot , trunk arteriosus , patent ductus arteriosus, and bicuspid aortic valve . In addition, several cases of HCM coexisting with abnormal coronary origin but not SCA have been reported in the literature[4–6]. Therefore, the current case was first reported in the literature which provides evidence for the coexistence of HCM and single-vessel coronary anomalies.
Various rare courses of SCA can lead to accidental ligation or injury of important main vessels during cardiac surgery. Therefore, every cardiac surgeon and coronary angiographer should be familiar with the presence and anatomy of this congenital anomaly. Because of the rarity of this condition and the complications during surgery, it is recommended that coronary angiography should be performed routinely before cardiac surgery. In addition, SCA should also be paid attention to during cardiopulmonary bypass surgery because the myocardial protection was related to the strategy of cardioplegia perfusion. We discussed the coronary angiography and echocardiographic imaging data of the patient in detail before operation, and considered that there was no obvious abnormality of the aortic valve. Finally, we agreed that anterograde perfusion in the aortic root could be safe and effective, and direct perfusion of a single coronary artery would be performed when necessary. This article is only for individual cases, patients with the same disease need individual solutions. Our current case report provides the evidence for the coexistence of HCM and SCA, and looks forward to providing corresponding support for the recurrence of the same case in the future.