Introduction

Apical transient dyskinesia, also known as apical ballooning, stress cardiomyopathy, “broken heart” syndrome or Tako-tsubo cardiomyopathy is a newly recognized entity. It was first described in Japan by Sato et al₁,₂ in 1990, and later confirmed in other world locations and races₃,₄. This syndrome presents early features similar to acute coronary syndromes, including chest pain, elevation of myocardial necrosis markers, electrocardiographic alterations and segmental left ventricular dyskinesia/akinesia. The main characteristics are the presence of normal coronary arteries assessed by coronary angiography and rapid and complete resolution of segmental motion alterations₁,₂,₃,₄. Prognosis is excellent compared with classic myocardial infarction₅. Frequently but not always, stress episode (emotional or physical) is associated with the development of this process. Patients are more likely women₅. Its pathophysiology remains unclear, although several theories have been proposed. Its relationship with brain and cathecolamine cardiotoxicity disorders seems established₆. Even more, the previously described profile has been stressed by recently published, data as other than apical left ventricular motion alteration with midventricular₇,₈ basal involvement₉, biventricular₁₀ alterations and previous coronary artery disease₁₁.

This article provides, to our knowledge, the first description of this novel transient left ventricular abnormality variant.

Subjects And Methods

We report a new variant of transient left ventricular ballooning in a multicentric 6-patient-case series, presenting as inferior acute myocardial infarction. We investigated patients who met the following inclusion criteria (Mayo)₁₂: 1) Clinical presentation mimicking acute coronary syndrome; 2) Transient hypokinesis, akinesis, or dyskinesis of the left ventricular segments with main inferior involvement as assessed by ventriculogram; 3) Absence of significantly obstructive coronary disease or angiographic evidence of acute plaque rupture or thrombus.; 4) New ECG abnormalities (either ST-segment elevation and/or T-wave inversion) or elevated cardiac troponin.; 5) Absence of: brain or intracranial disease potentially responsible, pheochromocytoma, myocarditis, hypertrophic cardiomyopathy or previous coronary artery disease. Management was decided according to the currently STEMI and NSTEMI guidelines available. Cardiovascular risk factors and triggering factors were studied from a thorough chart review combined with a clinical and echocardiographic follow-up. The inferior involvement was determined after assessment by cardiac catheterization analysed by al least two cardiologists unaware of the purpose of this study.

Results

Patients´ characteristics: Patients´s features are shown in table 1. Mean age was 54 years (33-81). 4 were women (66%). Cardiovascular risk factors were present, al least one, in all patients. Clinical presentation was effort-chest pain in 2 patients and rest chest-pain in 4 of them. An emotional trigger factor was present in only two cases (33%). The onset of the pain was less than six hours in the majority (5/6) but one (number 3) of the patients reported a brief similar rest-pain 24 hours before.

Figure 1

Table 1: Clinical features.

Blood measurements: CK and troponin I were repeatedly determined. Tn I was elevated in all patients, CK in 5 of 6 (83%). Data are shown in Table 2.

Figure 2

Table 2: Myocardial necrosis markers and onset electrocradiographic findings.

Total elevated cholesterol levels (>5mmol/l) was only elevated in one patient. Thyroid hormones were determined in 5 of 6 patients and all were normal.

ECG: (Figure 1.) During their in-hospital stay, electrocardiographic alterations were displayed in all patients (table 2). 50 % presented ST elevation. One of them presented ST depression (>1,5mm) in V2-5 leads, which recovered after treatment and 66% showed negative T waves.

Figure 3

Figure 1: Case 6´s electrocardiograms. A: On admission; B 12h later; C: 15h later; D: 96 h later. E: Follow-up, 2 months later; F: Follow-up, 18 months later. E y F are the basal ECG before control-stress test. Both of them were normal.

Figure 4

Table 3: Cardiac Catheterisation findings

Cardiac catheterization findings: (Figure2) Cardiac catheterization was performed in all patients. 5 (83%) in the first 24 hours after admission.

The sixth patient underwent the angiogram 48 hours later. Coronary arteries were normal in all patients (6/6). Left ventricular segmental motion alterations were demonstrated in 100%. Data are shown in table 3.

Figure 5

Figure 2: Cardiac catheterization findings. Case 1 (A,B), 4 (C,D) and 6 (E,F) ventriculogram are shown. Images on the left are diastole (A,C,E) and on the right systole(B,D,F).

Outcome: All patients presented a Killip I class on admission and were discharged without problems. In stay-complications were: an intraventricular thrombus (number 4, discharged on anticoagulation therapy), a transient ischaemic attack cath-related (number 5) and various episodes of rest-pain solved with nitrates (number 6). Mean stay was 6,8 days (3-12 days). Left ventricular motion recovery was completely accomplished in all cases. Mean follow-up was 9.5 months (1-18). One patient suffered from various episodes of pain during follow-up (18 months, number 6) but both of the treadmill stress-test yearly-performed were conclusive negative. The most serious complication was in number 4, a marathon-runner man who continued with intense physical exercise (several kilometres/day training running). He was discharged on anticoagulation therapy because a thrombus in the left ventricle. Thrombus resolution was achieved but in the follow-up-echocardiogram a new segmental infero-apical alteration was discovered after previous normalization on discharge, five months before. This finding was confirmed by means of cardiac magnetic resonance as a necrotic zone with motion alterations. However, the patient remained asymptomatic.

Discussion

The Takotsubo myocardiopathy could represent an special form of left ventricular stunning, including a mild form of myocardial infarction. The pathophysiology remains unclear although several theories have been proposed: anatomic coronary alterations₁₃; left ventricular outflow tract obstruction₁₄; coronary microvascular dysfunction; vasospasm, evanescent intracoronary thrombus, myocarditis and catecholamine excess (brain-stress related)₆.

In order to standardize diagnosis, various clinical criteria have been proposed. Our cases fulfilled Mayo criteria₁₂, even though they were proposed for the typical Takotsubo. Although the apical affectation (Takotsubo classical or typical form) remains the most frequent transient cardiomyopathy of this type₁₅, the recent publication of new variants of transient myocardial dyskinesia arises new questions about this syndrome₇,₈,₉,₁₀,₁₁,₁₅.

Our aim presenting this case-series was to remark that other left ventricular segments could be transiently affected, in the same manner that classical acute myocardial infarction can. This inferior variant may probably be related to the classical apical ballooning. It could represent a variant properly (inferior ECG alterations support that point) or the evolution to resolution of a typical case, although the ventriculograms were performed quite early after the onset of symptoms.

In ischemic cardiomyopathy it is well known that different segmental motion can be seen, depending on the coronary artery altered. Recently, Kurowski et al. reported that Scintigraphy and PET studies showing an strong correlation between location of wall motion abnormality and myocardial metabolism defects with a significantly higher apical decrease in glucose uptake in patients with a “typical” Takotsubo pattern compared with midventricular variant₈. Likewise, a relationship between Takotsubo and ischemic cardiomyopathy is being recognised₁₁. Therefore, it is possible we can not rule out Takotsubo and its variants to be a variant itself of ischemic cardiomyopathy, with mild anatomic or transient lesion assessed by angiogram but with functional repercussion.

Takotsubo cardiomyopathy, even if it is supposed to carry a very good prognostic₅ is not lacking of complications. In fact, 2 of our 6 patients suffered mild in-stay complications (33%). On the other hand, 1 patient suffered complications related to the cathetherization. Of note, is the interesting question raised by the silent myocardial infarction presented by one patient, the marathon-runner, during intense exercise, after a first transient episode. After that, It could be advisable to avoid extreme physical exercise, sometime, perhaps a month after the admission.

To conclude, further studies about this entity are needed in order to develop adequate management and preventive strategies.

Correspondence to

Dr. Iván Javier Núñez Gil. Avda. del TALGO 83, 1ºE. 28023 Aravaca, Madrid. Spain. Europe. 913307645 Fax 913303730 ibnsky@yahoo.es