Due to page limitations, we recognize that we have not included all the excellent scientific work completed in the area of alcohol and the cardiovascular system. Furthermore, there are conflicting data among studies regarding the prognosis of the condition, with some showing overall mortality near 60% and others showing a mortality rate of only 19% (Table 1). Despite these features, the structural changes do not seem to be specific, furthermore, they are not qualitatively different from those found in idiopathic DCM and they do not allow us to differentiate between the two conditions44. It also appears that the changes emerging in ACM patients only differ from idiopathic DCM in quantitative terms, with histological changes being more striking in idiopathic DCM than in ACM44.
- In all ACM studies, inclusion of patients is based on patients’ self-reported alcohol drinking habits, which may lead to an underestimation of the prevalence of ACM together with problematic identification of patients who abstain and those who continue drinking.
- Since myocardium requires a high energy supply to maintain persistent sarcomere contractions, it was supposed that alcohol could exert its damaging effect on the mitochondrial energy supply system, with the disruption of oxidative control mechanisms 26,100.
- Future studies to further characterize the role of different genotypes will help indentify those genotypes are more susceptible to chronic alcohol consumption.
- In patients with dilated cardiomyopathy, if additional questions remain after a history is obtained and noninvasive testing is performed, cardiac catheterization may be used to help exclude other etiologies of heart failure.
- When it comes to wine, one drink is defined as a 5-ounce (148 ml) serving, which typically contains about 12% ABV.
5. Sarcomere Damage and Dysfunction in ACM
The mainstay of therapy for alcoholic cardiomyopathy (AC) is to treat the underlying cause, ie, to have the patient exercise complete and perpetual abstinence from all alcohol consumption. The efficacy of abstinence has been shown in persons with early disease (eg, prior to the onset of severe myocardial fibrosis) and in individuals with more advanced disease (see Prognosis). Cardiac percussion and palpation reveal evidence of an enlarged heart with a laterally displaced and diffuse point of maximal impulse. Auscultation can help to reveal the apical murmur of mitral regurgitation and the lower parasternal murmur of tricuspid regurgitation secondary to papillary muscle displacement and dysfunction. Pulmonary rales signify pulmonary congestion secondary to elevated left atrial and left ventricular end-diastolic pressures. Jugular venous distention, peripheral edema, and hepatomegaly are evidence of elevated right heart pressures and right ventricular dysfunction.
4. The dose-Related Effect of Ethanol and Beverage Types on the Heart
During the first half of the 20th century, the concept of beriberi heart disease (ie, thiamine deficiency) was present throughout the medical literature, and the idea that alcohol had any direct effect on the myocardium was doubted. Epidemics of heart failure in persons who had consumed beer contaminated with arsenic in the 1900s and cobalt in the 1960s also obscured the observation that alcohol could exhibit a direct toxic effect. In the 1950s, evidence began to emerge that supported the idea of a direct toxic myocardial effect of alcohol, and research during the last 35 years has been particularly productive in characterizing the disease entity of alcoholic cardiomyopathy (AC).
Patterns of Drinking: Binge Drinking
- This review will provide an updated view of this condition, including its epidemiology, pathogenesis, diagnosis, and treatment (Graphical Abstract).
- The population was divided into 3 groups according to their intake volume during the follow-up period.
- Also, others have suggested that, in data from animal models of alcoholism, there is an interaction between chronic ethanol consumption and caloric deprivation in eliciting alterations in myocardial energy metabolism (58).
This was interpreted by the authors as suggesting that acetaldehyde plays a key role in the cardiac dysfunction seen after alcohol intake. Others have suggested that an acute decrease in mitochondrial glutathione content may play a role in mitochondrial damage and implicate oxidative stress as a contributor in this process. Mitochondrial dysfunction has a significant role in the development and complications of alcoholic cardiomyopathy 64, 65,70.
- All of these latter changes were prevented by the administration of either Valsartan (angiotensin II receptor blocker, 5mg/kg/d) or carnitine (antioxidant, 2 g/d), suggesting a role for angiotensin II and oxidative stress (30).
- Khanna et al. demonstrated that inducible nitric oxide synthase (iNOS) is increased in cardiomyocytes isolated from rats exposed to 1 month of ethanol (13 g/day, Lieber-DeCarli diet) (42).
- Unfortunately, it is well known that abstinence is difficult to achieve, and it is important to stress that alternative treatments are needed, including therapies to help with alcohol withdrawal, heart failure drugs, and other promising therapeutic approaches that focus on pathogenesis.
In fact, patients with ACM who abstain from alcohol have a better long-term prognosis than subjects with idiopathic dilated CMP 54. Out of end-stage cases, the majority of subjects affected by ACM who achieve complete ethanol abstinence functionally improve 33,82,135. The percentage of effective abstinence achievement on these patients submitted to specific programs ranges from 50% to 60% 8,9.
Histologic Findings
In fact, mitochondrial structural changes have been described in chronic alcohol consumers, with swollen megamitochondria and the distortion of inner cristae 107,108. Functionally high ethanol produces disruptions in the myocyte oxidative pattern and decreases in Complex I, II, and IV of the mitochondrial respiratory chain 100,109,110. As a reflection of this metabolic derangement, cytoplasmic lipid droplets and glycogen deposits appear.
In light of the available data, new studies will help to clarify the current prognosis of ACM compared to DCM and to determine prognostic factors in ACM that might differ from known prognostic factors in DCM. The first study, which specifically focused on the amount of alcohol necessary to cause ACM, was conducted by Koide et al20 in 1975. The authors examined the prevalence of cardiomegaly by means of chest x-rays and related it to alcohol alcohol cardiomyopathy consumption among a consecutive series of Japanese males of working age. They found that 2 of the 6 individuals (33%) whose alcohol consumption exceeded 125 mL/d had cardiomegaly.
Also, current common cardiac therapies such as ICD and CRT devices were not used because of what is Oxford House the period when the study was conducted. After a follow-up period of 47 mo, a significantly higher survival rate was observed among patients with DCM compared to patients with ACM. In their autopsies, he described finding dilated cavities of the heart and fatty degeneration of the ventricular walls14.