Sleep apnea may disrupt breathing, lowering oxygen levels and affecting heart rhythm. These disruptions might cause bradycardia or tachycardia in extreme situations. These disruptions may raise the risk of heart attacks and arrhythmias, even if the heart doesn't "stop" in the literal sense. Modalert 200mg (modafinil) may help control daytime drowsiness caused by sleep apnea, but it does not treat the disease. CPAP therapy, lifestyle adjustments, and other sleep apnea treatments may enhance heart health and well-being. If you suspect sleep apnea, visit a doctor for diagnosis and treatment.