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Dynamic Takotsubo Syndrome

Both Takotsubo cardiomyopathy and spontaneous coronary artery dissection (SCAD) of the distal portion of the left anterior descending artery affect the apical myocardium. It is important to distinguish between both diseases, because therapy and follow-up differ. Revascularization may be lifesaving in SCAD, whereas heart failure management is vital in Takotsubo cardiomyopathy. (Level of Difficulty: Intermediate.)


LEARNING OBJECTIVES
To examine the distal location of SCAD in middle-aged women with nonobstructive, nonatherosclerotic coronary arteries and wall motion abnormalities consistent with TC. To be aware of the dynamic nature of coronary pathology seen in patients with SCAD who have recurrent chest pain and have had an initial diagnosis of TC. To understand that treatment and prognosis of SCAD and TC differ: single antiplatelet therapy and beta blockers are used in SCAD, whereas ACE inhibitors are the treatment of choice in TC. MANAGEMENT. The patient was treated medically with low-dose aspirin, an ACE inhibitor, spironolactone, and beta-blockers. TTE on the day of discharge (day 18) showed a nearly full recovery of the global and regional left ventricular functions. The patient was discharged in good health.     Figure 1.   The third angiogram of Patient 1 shows complete resolution of lesion in the LCX (white arrows). Abbreviations as in Figure 1.  MANAGEMENT. The patient was treated medically with low-dose aspirin. She was already taking ACE inhibitors, spironolactone, and beta-blockers.

DISCUSSION
SCAD is a noniatrogenic separation of the coronary arterial wall. The underlying mechanism has yet to be elucidated, but an intimal tear or bleeding of the vasa vasorum could be the driving force (1), leading to a false lumen with intramural hematoma (2).
Until recently, SCAD was considered a rare disease, primarily seen in young women during the peripartum period and in patients with connective tissue disorders. The emergence of high sensitivity biomarkers and the use of intracoronary imaging have The second angiogram of Patient 2 shows type IIb SCAD of the first diagonal branch of the LAD (white arrows). Abbreviations as in Figure 1. When SCAD Hides in a Pot changed our mindset. A recent multicenter prospective observational study (3) showed that SCAD predominantly affects young to middle-aged women (mean age: 52 years old). FMD was seen in one-third of the patients, and peripartum SCAD or association with other connective diseases was rare. Emotional stress was reported in 50.3% and physical stress in 28.9% of patients. The association between SCAD (4) and FMD has recently been confirmed at a genetic level (4,5). A common variant of chromosome 6 at the PHACTR1 locus could be a risk locus for SCAD and FMD.
Because shear stress may be the driving force for SCAD, medical therapy with beta-blockers and singleantiplatelet therapy is the treatment of choice.
Revascularization is needed in some cases of SCAD patients who have ongoing ischemia (6), in contrast to TC, where treatment is based on the acute presentation of the disease, management of heart failure or in some cases shock. The role of long-term therapy with ACE inhibitors and beta-blockers is not well established.

CONCLUSIONS
This paper describes 2 cases of SCAD which were initially misdiagnosed as TC. These cases underscore the need for interventionists to familiarize themselves with the often subtle and sometimes hard to recognize angiographic appearance of SCAD. These cases also emphasize the fact that one should at all times be prepared to challenge an initial diagnosis and use additional imaging if deemed necessary. We clinicians should be aware of dynamic coronary pathology in SCAD.