Strokes on Left Raise Risk of Sudden Death

Strokes that involve the left side of the brain or both sides may raise the risk of death caused by a sudden heart stoppage, new research suggests. In contrast, strokes involving the right side are not linked to this risk. These findings run counter to previous reports that have shown an increased risk with right-sided, not left-sided, strokes, lead author Dr. Ale Algra, from University Medical Center Utrecht in the Netherlands, and colleagues note. This difference could relate to the fact that most of the earlier reports looked at the early phases of stroke, while the present study investigated the long-term effects, they add. The current results, which are reported in the medical journal Stroke, are based on a study of 2778 patients with “plaques” in the arteries that feed the brain. The subjects included 1483 patients who experienced at least one stroke in the past and 1295 with no history of stroke. On average, the patients were followed for 5 years. The risk of sudden death was 5.3 percent for patients without a stroke, 8.8 percent for those with left-sided strokes, 6.0 percent for those with right-sided strokes, and 9.7 percent for those with strokes on both sides of the brain. After accounting for other related factors, left-sided stroke raised the risk of sudden death by 45 percent compared with no stroke. Similarly, stroke on both sides was associated with a 40 percent rise in the risk. In contrast, right-sided infarction did not seem to increase the risk. Handedness was an important determinant of sudden death risk, the authors found. Left-handed or ambidextrous patients were 76 percent less likely to experience sudden death than their right-handed peers. The reason why stroke promotes sudden death is not completely understood, but it may involve a disturbance in how the brain controls the heart, the researchers state. “Left-handers may have a more distributed (nerve) network in the brain,” so that any one stroke is unlikely to disturb the heart, they add. “Our findings may have clinical implications,” the authors note. For example, they suggest that beta-blockers — drugs that can help prevent sudden death due to disturbances in heart rhythm — might be considered in patients with left-sided strokes. SOURCE: Stroke, December 2003.

Strokes that involve the left side of the brain or both sides may raise the risk of death caused by a sudden heart stoppage, new research suggests. In contrast, strokes involving the right side are not linked to this risk. These findings run counter to previous reports that have shown an increased risk with right-sided, not left-sided, strokes, lead author Dr. Ale Algra, from University Medical Center Utrecht in the Netherlands, and colleagues note. This difference could relate to the fact that most of the earlier reports looked at the early phases of stroke, while the present study investigated the long-term effects, they add. The current results, which are reported in the medical journal Stroke, are based on a study of 2778 patients with “plaques” in the arteries that feed the brain. The subjects included 1483 patients who experienced at least one stroke in the past and 1295 with no history of stroke. On average, the patients were followed for 5 years. The risk of sudden death was 5.3 percent for patients without a stroke, 8.8 percent for those with left-sided strokes, 6.0 percent for those with right-sided strokes, and 9.7 percent for those with strokes on both sides of the brain. After accounting for other related factors, left-sided stroke raised the risk of sudden death by 45 percent compared with no stroke. Similarly, stroke on both sides was associated with a 40 percent rise in the risk. In contrast, right-sided infarction did not seem to increase the risk. Handedness was an important determinant of sudden death risk, the authors found. Left-handed or ambidextrous patients were 76 percent less likely to experience sudden death than their right-handed peers. The reason why stroke promotes sudden death is not completely understood, but it may involve a disturbance in how the brain controls the heart, the researchers state. “Left-handers may have a more distributed (nerve) network in the brain,” so that any one stroke is unlikely to disturb the heart, they add. “Our findings may have clinical implications,” the authors note. For example, they suggest that beta-blockers — drugs that can help prevent sudden death due to disturbances in heart rhythm — might be considered in patients with left-sided strokes. SOURCE: Stroke, December 2003.