Today we discussed 2 cases – Case 1 was a middle aged man with a history of heavy EtOH consumption who presented with new onset heart failure. We discussed our approach to heart failure with a specific focus on alcoholic cardiomyopathy. Case 2 was an elderly man who developed distributive shock following his CABG surgery. We discussed our approach to shock and ultimately discussed the diagnosis of “vasoplegic syndrome.”
- Alcoholic cardiomyopathy is an acquired, dilated cardiomyopathy that may be at least partially reversible with abstinence from alcohol.
- Vasoplegic syndrome is a state of refractory, distributive shock that most commonly occurs in patients post CABG. Often, these patients are unresponsive to steroids & numerous vasopressor agents.
- Methylene blue is a well described alternative treatment for vasoplegic syndrome!
- It is a type of acquired, dilated cardiomyopathy associated with long-term heavy alcohol consumption (>80 g per day over at least 5 years).
- Pathogenesis is not fully understood, although acetaldehyde (toxic metabolite of alcohol) has been thought to lead to impaired calcium ion homeostasis, and oxidative damage of myocytes.
- The diagnosis is one of exclusion in a patient with features of dilated cardiomyopathy and a long history of heavy alcohol use and no other identified cause.
- Echo shows pronounced LV dilation, increased LV mass, thin walls, diastolic dysfunction, and systolic impairment.
- Is Alcoholic cardiomyopathy reversible?
- Recovery of cardiac function CAN occur if diagnosed early and further alcohol intake is halted.
- Small observational studies have shown improvement of LV function in patients who abstain. In a small French study of 9 patients with alcoholic cardiomyopathy, all 9 had significant improvement in LVEF (mean of 37%) with abstinence at 6 months.
- No marker for reversibility has been identified. Some studies have cited lack of myocardial interstitial fibrosis as a potential indicator of reversibility, but in our patient’s case, he had remarkable recovery of LV function even with evidence of interstitial fibrosis on endomyocardial biopsy.
Vasoplegic syndrome (VPS)
- Post-perfusion syndrome characterized by low SVR and high cardiac output within the first 4 postoperative hours. Typically, the hypotension is refractory to catecholamine therapy.
- Most commonly seen post CABG surgery, but can occur during any anesthetic. Pathophysiology is not completely understood, but involves the dysregulation of vascular tone secondary to systemic inflammation post cardiac surgery.
- Interestingly, usage of renin-angiotensin system (RAS) antagonists have been associated with vasoplegic syndrome.
- Normally, BP is maintained via 3 systems: sympathetic system, renin-angiotensin system, and vasopressinergic system.
- Anesthetics reduce the influence of sympathetic system of cardiovascular tone.
- Hence, under general anesthesia, there is an increased reliance on the RAS and the vasopressinergic system to maintain BP. RAS antagonists such as ACEI and ARBs block the RAS response to hypotension!
- Supportive care and pressors are the first line of treatment
- Methylene blue (MB) is a well described alternative treatment for VS! It interferes with the nitric oxide (NO)-cGMP pathway, inhibiting its vasorelaxant effect on smooth muscle. -However, beware of the side effects (arrhythmias, increased pulmonary vascular resistance, decreased renal and mesenteric blood flow, methemoglobinemia, hemolysis)