She was born with a weak heart.

她生来就有一个衰弱的心脏。

《牛津词典》

She suffered from a weak heart.

她心脏不好。

《牛津词典》

She tired easily and had a weak heart.

她容易疲劳，心脏也比较弱。

《柯林斯英汉双解大词典》

They may have a weak or damaged heart, high blood pressure or other problems of the blood system.

VOA: special.2010.07.27

He had a weak heart but a sharp mind.

FORBES: Magazine Article

Dr. Frank Stegall, a cardiologist at Redmond Regional Medical Center in Rome, told Gonzalez he had a chronically weak heart, or dilated cardiomyopathy.

CNN: Guatemalan in Atlanta awaits word on possible heart transplant

The heart disease study found a weak association between BPA and heart disease but it excluded six people who had the highest BPA concentrations.

FORBES: Connect