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🌱 來自: dilated cardiomyopathy

etiologies of dilated cardiomyopathy

(JACC 2021;77:2551; can also be prior myocarditis, vide infra)

Familial/genetic (>35%)

• Pt & ≥2 closely related family members w/ unexplained DCM;
• ~30 genes identified to date, encoding structural & nuclear proteins (eg, titin)

Idiopathic (<20%)

? undx infectious, EtOH, or genetic cause; ¼ w/ e/o DCM in relative

Toxic

• alcohol (~20%) typ. 7–8 drinks/d × >5 y, but variable;
• cocaine;
• XRT (usu Restrictive Cardiomyopathy);
• anthracyclines (risk ↑ >550 mg/m2, may manifest late),
• CYC
• trastuzumab,
• TKIs

Infiltrative (5%)

• typically RCMP (qv), but can be DCMP with thickened walls
• amyloidosis,
• sarcoidosis,
• hemochromatosis,
• tumor

Peripartum

(onset last mo → 5 mo postpartum; JACC 2020;75:207):

• ~1:2000
• ↑ risk w/ multip, ↑ age, Afr Am;
• stnd HF Rx (if preg, no ACEI or spironolact.);
• ~30% recur w/ next preg

Stress-induced (Takotsubo = apical ballooning)

• typically postmenopausal ♀
• mimics MI (chest pain, ± STE & ↑ Tn; deep TWI & ↑ QT)
• mid/apex dyskinesis;
• ? Rx w/ βB, ACEI; usually improves over wks (JAMA 2011;306:277).
• In-hosp morb/mort similar to ACS (NEJM 2015;373:929).

Tachycardia (JACC 2019;73:2328)

• likelihood ∝ rate/duration; often resolves w/ rate cntl

Arrhythmogenic right ventricular cardiomyopathy (ACM/ARVC)

• fibrofatty replacement of RV → dilation (dx w/ MRI);
• ECG: ± RBBB, TWI V1–V3, ε wave; VT risk (NEJM 2017;376:61)

LV noncompaction (Lancet 2015;386:813)

• prominent trabeculae, arrhythmias, cardioemboli

Metab/other

• hypothyroidism
• acromegaly
• pheochromocytoma, obstructive sleep apnea
• Vit B1
• selenium or carnitine deficiency