Contrast echocardiography reveals apparently normal coronary perfusion in a rat model of stress-induced (Takotsubo) cardiomyopathy

AIMS

Stress-induced cardiomyopathy (SIC) is an important differential diagnosis to acute myocardial infarction (AMI) that is associated with significant morbidity and mortality. The typical hallmark of SIC is left-ventricular apical akinesia but preserved function in basal segments. Catecholamines are postulated to play an important role in SIC but the precise pathophysiology is incompletely understood. Whether myocardial perfusion of the affected segments is impaired in SIC has been debated and remains unknown.

METHODS AND RESULTS

Myocardial contrast echocardiography (MCE) was used to study regional myocardial perfusion in a rat model of SIC. Twelve rats received 50 mg/kg isoproterenol (ISO) i.p. and were continuously monitored by MCE. Apical and basal perfusion were estimated and expressed as a ratio at baseline, 5, 10, 20, 30, 40, 50, 60, 70, 80, and 90 min post-ISO. The rats developed typical apical ballooning after 43 ± 9 min post-ISO injection. The ratio of apical:basal perfusion was close to 1.00 at all time-points and never dropped below 0.89 (95% CI never extended below 0.73). Light and electron microcoscopical investigation revealed no structural damage of myocardial vessels.

CONCLUSION

Apical perfusion is not impaired in the early phase of SIC in this rat model.

Tako-tsubo Syndrome in Men: Rare, but With Poor Prognosis

INTRODUCTION AND OBJECTIVES

Tako-tsubo syndrome is a potentially serious disease during the acute phase. It mimics myocardial infarction, but with no potentially causative coronary lesions. The aim of this study was to analyze the clinical course and outcome of patients with tako-tsubo syndrome by sex.

METHODS

We analyzed the characteristics of patients included in the RETAKO registry from 2003 to 2015, a multicenter registry with participation of 32 Spanish hospitals.

RESULTS

Of 562 patients included, 493 (87.7%) were women. Chest pain was less frequent as an initial symptom in men than in women (43 [66.2%] vs 390 [82.8%]; P < .01). The prognosis was worse in men, with higher in-hospital mortality (3 [4.4%] vs 1 [0.2%]; P < .01), longer intensive care stay (4.2 ± 3.7 vs 3.2 ± 3.2 days; P = .03) and a higher frequency of severe heart failure (22 [33.3%] vs 95 [20.3%]; P = .02). However, dynamic obstruction at the left-ventricular outflow tract occurred exclusively in women (39 [7.9%] vs 0 [0.0%]; P = .02). The incidence of functional mitral regurgitation was also higher in women (52 [10.6%] vs 2 [2.9%]; P = .04).

CONCLUSIONS

Tako-tsubo syndrome shows wide differences by sex in terms of its incidence, presentation, and outcomes. Prognosis is worse in men.

Delayed multifocal recurrent stress-induced cardiomyopathy after antidepressants withdrawal

Stress-induced cardiomyopathy is an acute disease characterized by a large left ventricular apical dyskinesia ("apical ballooning"), triggered by intense emotional or physical stress, acute illnesses or, rarely, by alcohol or opiates withdrawal. Connection to stress and apical asynergy suggest a catecholamine-mediated pathogenesis. We recently observed a typical apical stress-induced cardiomyopathy, arising two weeks after a long-lasting antidepressant treatment withdrawal and recurring, a week later, with evidence of inferior wall akinesia. The reported case has several unusual features: 1) both episodes were not preceded by relevant triggering event (except antidepressant discontinuation); 2) early heterozonal relapse was observed; 3) the latency between antidepressant discontinuation and stress-induced cardiomyopathy onset is unusually long. The lack of relevant triggering stress and the evidence of multifocal asynergies could support the hypothesis of a non-catecholaminergic pathogenesis. Moreover, the long latency after antidepressant withdrawal may suggest that prolonged antidepressant treatments may have delayed pathological consequences, possibly related to their known neuroplastic effects.

[Extracorporeal membrane oxygenation support for tako-tsubo syndrome after urgent caesarean section]

Tako-tsubo syndrome is a rare cardiomyopathy secondary to catecholamine toxicity responsible of myocardial stunning. Severe complications such as cardiogenic shock or ventricular arrhythmia can occur. We presented the case of a 32-year-old woman victim of a tako-tsubo syndrome with severe cardiogenic shock during surgical procedure for urgent caesarean section. After refractory haemodynamic failure, the patient benefits from extracorporeal membrane oxygenation support device with success.

Discrepant myocardial microvascular perfusion and mechanics after acute myocardial infarction: Characterization of the "Tako-tsubo effect" with real-time myocardial perfusion contrast echocardiograph

BACKGROUND

In patients with acute anterior myocardial infarction (MI), sometimes an "apical ballooning" contractile dysfunction pattern that exceeds factual myocardial injury is identified in the ventriculography and bedside echocardiography. The hemodynamic consequences/sequela of this "Tako-tsobu effect" has not been well delineated. Of note, this anatomic imaging finding often misleads frontline physicians who assume reciprocal causation of persistent cardiac pump failure and ventricular pressure overload.

METHODS AND RESULTS

Using real-time myocardial perfusion contrast echocardiography (MCE), we investigated myocardial (microvascular) perfusion in 60 patients after acute MI and coronary revascularization. Twenty-eight percent of the studied patients showed significantly mismatched myocardial perfusion and contractile defects. In these patients, an integrated imaging assessment with coronary angiography/ventriculography, deformation echocardiography, and MCE proved that the myocardial mechanic abnormalities significantly exceeded the defected perfusion areas. Compared with 72% of the patients without perfusion-contractility mismatch, apparently worse systolic functions (left ventricular ejection, wall motion score, and systolic longitudinal strain) in these patients did not change diastolic ventricular filling pressures (E/E' and E/A) or hemodynamic consequences/adverse events. Both systolic and diastolic functions in patients with perfusion-contractility mismatch appeared to be comparable with those in patients with Tako-tsubo syndrome.

CONCLUSIONS

Real-time MCE identifies discrepant myocardial microvascular perfusion and mechanics in patients with acute MI. The "Tako-tsubo effect" in patients with perfusion-contractility mismatch does not cause diastolic filling pressure change or worse hemodynamic consequence/cardiac event.

[Tako-tsubo syndrome: analysis of a series of 60 cases]

BACKGROUND AND OBJECTIVE

The Tako-tsubo syndrome (TS) is a reversible acute cardiomyopathy simulating an infarction. We analyzed 60 patients admitted with TS in our center.

PATIENTS AND METHOD

A percentage of 73.3 were women (mean age: 70.6 ± 11.8 years); 83.3% had some cardiovascular risk factor, 25% had an anxiety-depressive disorder and in 58.3% a precipitating factor was identified, emotional stress being the most frequent. A percentage of 15.3 showed complete left bundle branch block (LBBB). In 23.3% of patients, contractile abnormalities respected the apex (mid ventricular or diaphragmatic types).

RESULTS

The anterior descending artery showed no significant lesions in 35% of patients and in 68.3% it had a diaphragmatic segment. Forty percent of patients developed heart failure (HF) and 18.3% cardiogenic shock (CS). The overall in-hospital mortality was 3.3%, while it was 8.3% among those patients who developed HF. The incidence of CS was higher among patients with LBBB (44.4 vs. 13.7%, P=.05) and males (43.8 vs. 9.1%, P=.005).

CONCLUSIONS

Although in-hospital mortality in patients admitted due to TS is low, a significant percentage of these patients develop HF with a high mortality in this subgroup. Males and patients with LBBB had higher in-hospital morbidity.

Prognostic value of the Tpeak-Tend interval for in-hospital subacute ventricular arrhythmias in tako-tsubo syndrome

INTRODUCTION AND OBJECTIVES

The clinical value of electrocardiogram (ECG) repolarization parameters associated with ventricular arrhythmias (VAs) in tako-tsubo syndrome is still under debate. We aimed to evaluate ECG predictors of subacute VAs, defined as those occurring after the first 48hours from admission.

METHODS

This single-center observational study enrolled patients admitted to the cardiology department between 2012 and 2018 with a confirmed diagnosis of tako-tsubo syndrome. Data collection included a 12-lead ECG on admission and at 48hours, continuous telemetry monitoring, blood testing, transthoracic echocardiography, and coronary angiography during hospitalization. VAs events were defined as: premature ventricular contractions ≥ 2000 within a 24-hour window of telemetry monitoring, ventricular fibrillation, sustained ventricular tachycardia (VT), polymorphic VT, and non-sustained VT.

RESULTS

A total of 87 patients (age 72±12 years) were enrolled. During a median of 8 days of hospitalization, subacute VAs were documented in 22 patients (25%) after a median of 91hours from admission. Subacute VAs were associated with an increase in mortality during hospitalization (P=.030). The corrected global (mean of the 12-lead ECG values) Tpeak-Tend interval at 48hours from admission was an independent predictor of subacute VAs and was statistically superior to the standard corrected QT interval (Z test, P=.040). A cut-off of 108 msec for the corrected global Tpeak-Tend yielded a 71% sensitivity and 72% specificity for subacute VAs.

CONCLUSIONS

In patients with tako-tsubo syndrome, subacute VAs are associated with repolarization alterations that can be identified on conventional ECG using the Tpeak-Tend interval.

[Heart rate disorders in patients with Tako-tsubo syndrome]

OBJECTIVES

This study sought to evaluate the incidence, prognosis and treatment of heart rhythm disorders (HRD) in Tako-tsubo syndrome (TTS).

BACKGROUND

TTS is associated with HRD. The HRD prognostic value is not well characterized in TTS yet.

METHODS

The HRD of patients included in the National Registry of Tako-tsubo syndrome, admitted between 2002 and 2018 and coming from 38 hospitals throughout the country, was analyzed. We analyzed any heart rhythm disorder in patients presented before admission, at admission and in long-term follow-up.

RESULTS

All types of HRD were described in 259 (23.5%) cases, from a cohort of 1,097 consecutive patients with TTS. HRD was more associated with diabetes mellitus, smoking, hyperuricemia, sleep apnea, anemia with a worse LVEF on admission. The most frequent HRD was a new onset of atrial fibrillation. During hospitalization, patients with HRD showed more complications such as shock on admission, major bleeding, acute renal failure, and combined infections. At follow-up, they presented higher mortality and more major adverse cardiac events, but with a non-significant correlation.

CONCLUSIONS

The incidence of HRD in patients with TTS is not infrequent. TTS, when associated with HRD, presents more complications and a worse prognosis both in hospital and in the long term.

Rationale and design of the beta-blockers in tako-tsubo syndrome study: a randomized clinical trial (β-Tako)

INTRODUCTION Y OBJECTIVES

Tako-tsubo syndrome (TTS) is a cardiac condition that mimics acute coronary syndrome, characterized by transient left ventricular dysfunction in the absence of culprit coronary artery stenosis. Although its etiology remains unknown, reversible microvascular dysfunction secondary to an adrenergic surge is thought to play a role. Treatment is empirical, although most patients receive beta-blockers (BB) in clinical practice. The Beta-blockers in Tako-tsubo Syndrome study (β-Tako), is an academic, multicenter, pragmatic, prospective randomized open-label trial with blinded endpoint evaluation that aims to assess the efficacy and safety of BB in patients with TTS.

METHODS

The diagnosis of TTS will be confirmed by invasive coronary angiography and serial echocardiographic assessments. Two hundred patients with TTS will be randomized (1:1) to BB (n=100) or no BB (n=100). BB with alpha or nitric oxide release activity will be used in the treatment arm.

RESULTS

The primary efficacy endpoint is the comparison of the wall motion score index by echocardiography at 7 days, analyzed by an independent core laboratory. Changes in left ventricular ejection fraction and global longitudinal strain will also be evaluated. A composite clinical endpoint (death, stroke, admission for recurrent TTS, acute coronary syndrome, heart failure, or atrial fibrillation) at 1 year will be assessed by an independent clinical events committee. Several predefined substudies will be conducted to examine clinical, imaging, biomarker, pharmacogenetic, inflammatory, messenger ribonucleic acids, and quality-of-life parameters.

CONCLUSIONS

The β-Tako trial will generate robust scientific evidence to address unmet clinical needs and inform clinical and treatment decisions in this uniquely challenging clinical entity. The study has been registered (EU-CT number: 2023-510213-25-01, ClinicalTrials.gov Identifier, NCT06509074.