Delayed-contrast enhancement cardioresonance in transient left ventricular apical ballooning

Prevalence and signal characteristics of late gadolinium enhancement on contrast-enhanced magnetic resonance imaging in patients with takotsubo cardiomyopathy

BACKGROUND

To determine the prevalence and signal intensity (SI) characteristics of late gadolinium enhancement (LGE) on magnetic resonance imaging (MRI) in takotsubo cardiomyopathy (TC).

METHODS AND RESULTS

Cine, black-blood T2-weighted and LGE MR images were acquired in 23 patients with TC within 72 h of onset. Wall motion abnormality (WMA), edema and LGE were evaluated with a 16-segment model. The SI characteristics of LGE were analyzed using SI distribution in remote normal segments as reference. Follow-up MRI was performed 3 months later. Retrospective analysis of LGE MRI was also performed in 10 patients with acute myocardial infarction (AMI) to compare the SI characteristics between TC and AMI. In acute phase, WMA and edema were observed in 236 (64%) and 205 (56%) of 368 segments. LGE was observed in 10 (2.7%) of 368 segments and in 5 (22%) of 23 patients. All LGE lesions in TC exhibited transmural enhancement. The contrast-to-noise ratio (CNR) in TC was significantly lower than that of AMI (3.1±0.3 standard deviations (SD) vs. 6.1±1.2 SD, P<0.01), and CNR value of 4 was useful for distinguishing TC from AMI. Both LGE and WMA disappeared within 12 months.

CONCLUSIONS

Grey myocardial signal on LGE MRI may be observed in patients with TC. However, the extent of LGE is substantially less than that of WMA and edema, and disappears within 12 months.

Takotsubo cardiomyopathy--a clinical review

Stress cardiomyopathy is characterised by reversible left ventricular dysfunction. It simulates an acute coronary syndrome (ACS), presenting with precordial pain or dyspnoea, changes of the ST segment, T wave, or QTc interval on electrocardiogram, and raised cardiac enzymes. Typical findings are disturbances of segmental contractility (apical hypokinesia or akinesia), with normal epicardial coronary arteries. The true prevalence is unknown, as the syndrome may be under-diagnosed; it is more common in postmenopausal women. There is usually a trigger in the form of physical or psychological stress. The electrocardiographic, echocardiographic, and ventriculographic changes resolve spontaneously over a variable period of time (from days to months). There are a number of pathophysiological theories, none of which has been shown to be definitive, suggesting that all of them may be involved to some extent. The prognosis is generally favourable, and recurrence is very rare.

Takotsubo cardiomyopathy: assessment with cardiac MRI

OBJECTIVE

The objective of this article is to show how MRI findings can be used to differentiate Takotsubo cardiomyopathy from acute coronary syndrome.

CONCLUSION

Takotsubo cardiomyopathy is a disorder that mimics acute coronary syndrome. MRI can show not only edema in the ventricular wall, which is diffuse and without arterial territory distribution, but also motion abnormalities with typical akinesis in the apical and mid planes. Moreover, MRI can detect potential complications such as obstruction of the left ventricular outflow tract or thrombus in the left ventricular cavity.

Cardiovascular magnetic resonance T2 signal abnormalities in left ventricular ballooning syndrome

Left ventricular ballooning syndrome (LVBS), also known as Takotsubo cardiomyopathy, is characterized by regional left ventricular dysfunction associated with severe psychological stress. T2 weighted cardiac magnetic resonance (CMR) can identify myocardial edema due to ischemia or other insults. A standard clinical CMR scan with double inversion recovery fast spin echo T2 weighted sequences was performed on consecutive patients with LVBS. T2 signal was compared in myocardial segments with normal and impaired function based on systolic wall thickening (SWT). Eight LVBS patients were identified, all female, with a median age of 61 years and median left ventricular ejection fraction of 52%. Four patients had apical ballooning and four had mid-wall or basal ballooning. In severely dysfunctional segments (those with SWT < 25%), the median percentage of high T2 signal was 85 compared with 35 in those with SWT > 25% (P < 0.001). When the segments were categorized into tertiles based on SWT, the percentage of high T2 signal was greatest in segments with the worst function (68% vs. 43% vs. 31%, P = 0.005). In the five patients who returned for follow up, there was a significant reduction in high T2 signal compared with baseline in those segments that were initially severely dysfunctional (85% vs. 35%, P < 0.001). In conclusion, we describe elevated T2 signal consistent with myocardial edema in patients with LVBS. The T2 signal is highest in myocardium with the most impaired function and resolves over time.

Immunohistological basis of the late gadolinium enhancement phenomenon in tako-tsubo cardiomyopathy

AIMS

Tako-tsubo cardiomyopathy is characterized by transient contractile dysfunction after emotional or physical stress. Only few patients show late gadolinium enhancement (LGE) in cardiovascular magnetic resonance imaging (MRI). It was the purpose of this study to elucidate the histological basis of this phenomenon.

METHODS AND RESULTS

The study included 15 patients. Tako-tsubo cardiomyopathy was diagnosed by coronary angiography and ventriculography. Cardiac MRI was performed within 24 h of admission. Endomyocardial biopsies were taken during the acute phase and after recovery. The content of fibrosis was determined by immunohistochemical staining of collagen-1. In the acute phase, cardiac MRI revealed LGE in five patients. This was completely reversed at follow-up [14, inter-quartile range (IQR) 11-14.5 days]. All patients showed a significant increase of collagen-1 compared with control tissue. Moreover, the amount of collagen-1 was significantly higher in LGE positive patients (LGE positive: 18.84, IQR 13.82-19.75 AU/microm(2); LGE negative: 7.57, IQR 5.41-9.19 AU/microm(2), P = 0.001). The presence of LGE was not associated with poorer left ventricular function.

CONCLUSION

The presence of LGE cannot rule out tako-tsubo cardiomyopathy. Instead it defines a special subgroup of patients with a disproportionate increase of extracellular matrix.

A new ECG criterion to identify takotsubo cardiomyopathy from anterior myocardial infarction: role of inferior leads

With the exception of contrast-enhanced cardiovascular magnetic resonance imaging, clear distinction of takotsubo cardiomyopathy from anterior wall myocardial infarction cannot be achieved currently by simple and noninvasive tests. The aim of this study was to examine the role of inferior ECG leads in distinguishing these two conditions. From January 2004 to June 2006, eight female patients suffering from takotsubo cardiomyopathy were identified by the Mayo Clinic criteria. The clinical and ECG features were compared with 27 consecutive sex- and age-matched patients with anterior wall myocardial infarction admitted to the Coronary Care Unit within the same period. The observed ECG features were then verified with that of 62 published cases of takotsubo cardiomyopathy. Takotsubo cardiomyopathy patients had similar left ventricular ejection fraction (35.0% +/- 5.7% vs 38.2% +/- 6.4%, P = 0.829), lower peak creatinine kinase level (461 +/- 330 U/l vs 2723 +/- 1826 U/l, P = 0.020), more ST-segment elevation in the inferior leads (50% vs 7.4%, P = 0.016), and virtually no ST-segment depression in inferior leads (0% vs 48.2%, P = 0.015) compared with patients who had anterior wall myocardial infarction. ST-segment elevation of >or=1.0 mm in lead II had 62.5% sensitivity and 92.6% specificity in detecting takotsubo cardiomyopathy. The observed ECG characteristics were comparable with those in the literature. In patients who present with anterior wall myocardial infarction, the absence of ST-segment depression or ST-segment elevation in inferior leads, especially if the ST-segment in lead II >or= III, is highly suggestive of takotsubo cardiomyopathy.

MRI for the diagnosis of left ventricular apical ballooning syndrome (LVABS)

To compare MRI findings of left ventricular apical ballooning syndrome (LVABS) with those of acute myocardial infarction (AMI). Fifteen patients with a LVABS (group 1) and 25 patients with an AMI (group 2) were explored by MRI within 24 h after admission. Comparison of both groups for the number and location of myocardial segments with abnormal wall motion and abnormal perfusion or delayed enhancement was performed. The number of involved segments was higher in group 1 than in group 2 (p<0.001). In group 1, segments with abnormal wall motion were distributed in more than one vascular territory in all patients and confined to the medial, distal, and apical regions of the left ventricle. Subendocardial hypoenhancement was observed in 16/25 patients (64%) in group 2 and in none of group 1 (p<0.001). All patients in group 2 demonstrated delayed-enhancement abnormalities in a vascular distribution, whereas none in group 1 presented this abnormality (p<0.001). Diffusely distributed segmental wall-motion abnormalities and absence of first-pass perfusion hypoenhancement and of delayed enhancement at MRI help to differentiate LVABS from AMI. In the acute phase or in some difficult cases, cardiac MRI should become routine to confirm the diagnosis of LVABS.

Levosimendan: the inotrope of choice in cardiogenic shock secondary to takotsubo cardiomyopathy?

Takotsubo cardiomyopathy (TC) has become an increasingly recognised entity in Western literature since its initial reporting in Japan. The pathogenesis underlying the myocardial stunning and systolic dysfunction is thought to be induced by elevated systemic levels of catecholamines and neuropeptides. Whilst the majority of patients are haemodynamically stable, a small proportion can develop cardiogenic shock. This creates a therapeutic dilemma because inotropic support using exogenous catecholamines (adrenaline, dobutamine, dopamine) may be counter-productive. Two cases where the calcium sensitiser levosimendan (a non-catecholamine inotrope) was used successfully in TC-related cardiogenic shock are presented. The management of circulatory compromise in TC is then discussed.