Pregnancy-related maternal deaths due to cardiovascular diseases in Japan from 2010 to 2019: an analysis of maternal death exploratory committee data.

Objective: Cardiovascular disease (CVD) is the leading cause of maternal deaths in high-income countries. This study aimed to assess the characteristics of maternal deaths due to CVDs and the quality of care provided to patients, and to identify elements to improve maternal care in Japan.

Methods: This descriptive study used the maternal death registration data of the Maternal Deaths Exploratory Committee of Japan between 2010 and 2019.

Results: Of 445 eligible pregnancy-related maternal deaths, 44 (9.9%) were attributed to CVD. The most frequent cause was aortic dissection (18 patients, 40.9%), followed by peripartum cardiomyopathy (8 patients, 18.2%), and pulmonary hypertension (5 patients, 11.4%). In 31.8% of cases, cardiopulmonary arrest occurred within 30 min after initial symptoms. Frequent symptoms included pain (27.3%) and respiratory symptoms (27.3%), with 61.4% having initial symptoms during the prenatal period. 63.6% of the patients had known risk factors, with age ≥35 years (38.6％), hypertensive disorder (15.9%), and obesity (15.9%) being the most common. Quality of care was assessed as suboptimal in 16 (36.4%) patients. Cardiac risk assessment was insufficient in three patients with preexisting cardiac disease, while 13 patients had symptoms and risk factors warranting intensive monitoring and evaluation.

Conclusion: Aortic dissection was the leading cause of maternal death due to CVDs. Obstetrics care providers need to be familiar with cardiac risk factors and clinical warning signs that may lead to impending fatal cardiac events. Timely risk assessment, patient awareness, and a multidisciplinary team approach are key to improving maternal care in Japan.