Stress Cardiomyopathy Definitively Presents with Regional Wall Motion Abnormalities
Yes, regional wall motion abnormalities (RWMAs) are a defining and essential feature of stress cardiomyopathy (Takotsubo cardiomyopathy). The presence of these abnormalities is required for diagnosis, though their pattern and distribution vary considerably among patients 1.
Characteristic Wall Motion Patterns
The European Heart Journal consensus document identifies four distinct RWMA patterns in Takotsubo syndrome 1:
Apical ballooning (most common): Hypo-, a-, or dyskinesia of mid-apical myocardial segments, sometimes with involvement of the anterior or entire interventricular septum, inferior wall, or midventricular anterolateral wall 1
Midventricular variant: Hypo-, a-, or dyskinesia of midventricular segments resembling a "cuff" pattern 1
Basal variant (rare): Only basal segments involved, commonly seen with subarachnoid hemorrhage, epinephrine administration, or pheochromocytoma 1
Focal variant: Typically involves an anterolateral segment, requiring cardiac MRI to differentiate from acute coronary syndrome or myocarditis 1
Critical Distinguishing Feature from Coronary Disease
The hallmark diagnostic criterion is that wall motion abnormalities extend beyond a single coronary artery territory 1, 2. This "circular" pattern of dysfunction at speckle-tracking echocardiography distinguishes Takotsubo from myocardial infarction 1. The American Society of Echocardiography and European Association of Cardiovascular Imaging explicitly state that regional wall motion abnormalities occur in stress-induced (Takotsubo) cardiomyopathy in the absence of coronary artery disease 1.
Quantitative Diagnostic Thresholds
A wall motion score index (WMSI) ≥1.75 with more than four dysfunctional segments identifies Takotsubo with 83% sensitivity and 100% specificity 1. Each segment should be scored as: (1) normal/hyperkinetic, (2) hypokinetic, (3) akinetic, or (4) dyskinetic 1.
Rare Exception: Forme Fruste Presentation
While extremely uncommon, one case report documented reversible stress cardiomyopathy with ST-elevation and troponin elevation but without regional wall motion abnormalities 3. However, this represents an atypical forme fruste variant and should not alter clinical practice—the absence of RWMAs should prompt reconsideration of the diagnosis 3.
Functional Characteristics That Aid Diagnosis
Basal hyperkinesis often accompanies apical ballooning, potentially causing dynamic left ventricular outflow tract obstruction in 20% of cases 1
Systolic lengthening (passive motion) occurs in Takotsubo rather than the longitudinal shortening seen in viable myocardium during STEMI 1
No improvement with low-dose dobutamine in early stages distinguishes Takotsubo from ischemic cardiomyopathy 1
Clinical Pitfall to Avoid
Do not dismiss the diagnosis of Takotsubo if wall motion abnormalities appear to follow a coronary distribution—up to 36% of patients may have concomitant coronary artery disease 4. The key is whether the extent of dysfunction is disproportionate to any coronary stenosis present and whether complete recovery occurs 5, 6.