In general, in the case of cardiac complications with an accompanying vascular anomaly, symptom-oriented medical therapy should be initiated as soon as possible to optimize cardiac function and oxygen consumption. Expert care by a cardiologist and, if appropriate, anesthesiologist is recommended.
However, cause-oriented treatment of the coexisting vascular anomaly is decisive. These are usually fast-flow arteriovenous malformations, which should be rapidly subjected to catheter angiography followed by embolization to rapidly occlude the multiple arteriovenous shunts. Patients with hereditary hemorrhagic teleangiectasia (HHT) with arteriovenous fistulas between the pulmonary artery and pulmonary vein should undergo timely embolization of the fistulas.
Depending on how long a fast-flow arteriovenous malformation has existed and its extent, there is an increase in cardiac output with initially left ventricular and during the disease course right ventricular increase in cardiac filling pressure. Often, early reduction of the hemodynamically relevant shunt volume by minimally invasive catheter embolization can avoid drug therapy for preload and afterload reduction in the presence of impending heart failure.
The basis of drug therapy is salt restriction and diuretics. Any parallel anemia must be optimally corrected. If atrial dilatation with arrhythmia is present, therapy of tachyarrhythmia or VHF should be performed. Because of the problems of beta blockers (see below), digitalis may also be used. The uncritical use of peripheral vasodilators in arteriovenous malformations (ACE inhibitors, phosphodiesterase inhibitors) must be carefully examined for its cardiac and circulatory effects, since it can often lead to a further increase in cardiac output. Beta blockers, however, are most critical in this regard because, in addition to peripheral vasodilation (with further lowering of peripheral vascular resistance), beta blockers also have negative inotropic and negative chronotropic effects. An increase in heart rate and cardiac output may be physiologically necessary to maintain the necessary peripheral tissue perfusion in the setting of multiple arteriovenous shunts and reduced peripheral flow resistance. Any further reduction of the peripheral flow, negative inotropic effect or reduction of heart rate, all of which are effects of beta blockers, may be detrimental.
Long-term anticoagulant therapy may also be necessary to minimize thromboembolic complications.