Takotsubo Cardiomyopathy: What we have Learned in the Last 25 Years? (A Comparative Literature Review)

Cardiac manifestations of prolonged seizure: A case report on reverse takotsubo syndrome and neurogenic stunned myocardium

Seizures, characterized by excessive electrical discharges in the brain, can lead to severe complications, including cardiac arrhythmias and Takotsubo syndrome, a form of stress-induced cardiomyopathy mimicking acute coronary syndrome. We present a case of a 66-year-old female with epilepsy and postcerebrovascular accident status who experienced a 45-minute seizure resulting in elevated troponin levels and ECG changes. Echocardiography revealed severe hypokinesia and hyperkinesia with a left ventricular ejection fraction of 30%-35%, and coronary angiography was normal, leading to the diagnosis of a variant of Takotsubo syndrome characterized by basal rather than apical dysfunction. The patient showed significant improvement after 96 hours in the coronary care unit following adjusted anti-seizure medications and supportive cardiac care. This case highlights the importance of recognizing and managing cardiac complications such as Takotsubo syndrome in patients with neurological events, emphasizing the need for close collaboration between neurology and cardiology to improve patient outcomes.

Takotsubo syndrome is a coronary microvascular disease: experimental evidence

BACKGROUND AND AIMS

Takotsubo syndrome (TTS) is a conundrum without consensus about the cause. In a murine model of coronary microvascular dysfunction (CMD), abnormalities in myocardial perfusion played a key role in the development of TTS.

METHODS AND RESULTS

Vascular Kv1.5 channels connect coronary blood flow to myocardial metabolism and their deletion mimics the phenotype of CMD. To determine if TTS is related to CMD, wild-type (WT), Kv1.5-/-, and TgKv1.5-/- (Kv1.5-/- with smooth muscle-specific expression Kv1.5 channels) mice were studied following transaortic constriction (TAC). Measurements of left ventricular (LV) fractional shortening (FS) in base and apex, and myocardial blood flow (MBF) were completed with standard and contrast echocardiography. Ribonucleic Acid deep sequencing was performed on LV apex and base from WT and Kv1.5-/- (control and TAC). Changes in gene expression were confirmed by real-time-polymerase chain reaction. MBF was increased with chromonar or by smooth muscle expression of Kv1.5 channels in the TgKv1.5-/-. TAC-induced systolic apical ballooning in Kv1.5-/-, shown as negative FS (P < 0.05 vs. base), which was not observed in WT, Kv1.5-/- with chromonar, or TgKv1.5-/-. Following TAC in Kv1.5-/-, MBF was lower in LV apex than in base. Increasing MBF with either chromonar or in TgKv1.5-/- normalized perfusion and function between LV apex and base (P = NS). Some genetic changes during TTS were reversed by chromonar, suggesting these were independent of TAC and more related to TTS.

CONCLUSION

Abnormalities in flow regulation between the LV apex and base cause TTS. When perfusion is normalized between the two regions, normal ventricular function is restored.

Transient stress-related hyperviscosity and endothelial dysfunction in Takotsubo syndrome: a time course study

Takotsubo syndrome (TTS) is an acute and usually reversible heart failure syndrome, frequently associated with emotional or physical stress. Its pathophysiology remains largely unclear, although several mechanisms related to catecholaminergic storm have been proposed. In this study we analyzed during the acute phase of TTS and at follow-up both hemorheological parameters and biomarkers of endothelial damage, whose time course has never been fully explored. In 50 TTS women, we analyzed several hemorheological parameters [whole blood viscosity (WBV) at 0.512 s^-1 and at 94.5 s^-1, plasma viscosity (PLV), erythrocyte deformability and aggregation index] as well as biomarkers of endothelial dysfunction [von Willebrand Factor (vWF), Plasminogen activator inhibitor-1 and factor VIII levels] during the acute phase and after a median 6 months follow-up. These variables were also assessed in 50 age-matched healthy women. Respect to follow-up, in the acute phase of TTS we observed higher values of white blood cell count, fibrinogen, WBV at low and high shear rates, PLV, erythrocyte aggregation index and lower values of erythrocyte elongation index. Moreover, all biomarkers of endothelial dysfunction resulted significantly higher in the acute phase. During follow-up WBV at 94.5 s^-1, erythrocyte elongation index and vWF resulted significantly altered with respect to controls. The results of this study confirm the role of hyperviscosity and endothelial dysfunction in TTS pathophysiology. Moreover, they suggest the persistence of alterations of erythrocyte deformability and endothelial dysfunction even beyond the acute phase that could be the target of therapeutic strategies also during follow-up.

Permanent Pacemaker Implantation in a Patient with Takotsubo Cardiomyopathy and Complete Atrioventricular Block

This case report presents a patient with Takotsubo cardiomyopathy (TCM) and complete atrioventricular (AV) block who was treated with permanent pacemaker implantation. A 78-year-old woman with a history of hypertension presented with a 6-month history of palpitations. On initial evaluation, her heart rate was 40 beats/minute. Electrocardiography revealed a complete AV block and T-wave inversion in these leads: I, II, aVL, aVF, and V3–6. Echocardiography showed akinesis from the midventricle to the apex and hyperkinesis on the basal segments. The patient was diagnosed with TCM and complete AV block. Because improvement of TCM may subsequently improve the AV node dysfunction associated with TCM, the patient was admitted for treatment of heart failure without pacemaker implantation. The left ventricular (LV) abnormal wall motion improved gradually; however, the AV block persisted intermittently. On hospital day 14, a pause of 5–6 seconds without LV contraction was observed, and permanent pacemaker implantation was performed. On day 92, echocardiography revealed normal LV wall motion. However, electrocardiography revealed that the pacemaker rhythm with atrial sensing and ventricular pacing remained. Although specific degree of damage that may result from AV block associated with TCM is unknown, some of these patients require pacemaker implantation, despite improvement of abnormality in LV wall motion.

Increased Catecholamine Levels and Inflammatory Mediators Alter Barrier Properties of Brain Microvascular Endothelial Cells in vitro

Recent studies have suggested a pathogenetic link between ischemic stroke and Takotsubo cardiomyopathy (TCM) with poor outcome, when occurring simultaneously. Increased catecholamine (CAT) levels as well as elevated inflammatory mediators (INF) are found in the blood of patients with ischemic stroke concomitant with Takotsubo syndrome (TTS). On molecular level, the impact of these stressors combined with hypoxemia could compromise the integrity of the blood brain barrier (BBB) resulting in poor outcomes. As a first step in the direction of investigating possible molecular mechanisms, an in vitro model of the described pathological constellation was designed. An immortalized murine microvascular endothelial cell line from the cerebral cortex (cEND) was used as an established in vitro model of the BBB. cEND cells were treated with supraphysiological concentrations of CAT (dopamine, norepinephrine, epinephrine) and INF (TNF-α and Interleukin-6). Simultaneously, cells were exposed to oxygen glucose deprivation (OGD) as an established in vitro model of ischemic stroke with/without subsequent reoxygenation. We investigated the impact on cell morphology and cell number by immunofluorescence staining. Furthermore, alterations of selected tight and adherens junction proteins forming paracellular barrier as well as integrins mediating cell-matrix adhesion were determined by RT-PCR and/or Western Blot technique. Especially by choosing this wide range of targets, we give a detailed overview of molecular changes leading to compromised barrier properties. Our data show that the proteins forming the BBB and the cell count are clearly influenced by CAT and INF applied under OGD conditions. Most of the investigated proteins are downregulated, so a negative impact on barrier integrity can be assumed. The structures affected by treatment with CAT and INF are potential targets for future therapies in ischemic stroke and TTS.

Frailty and cognitive impairment are predictive of takotsubo syndrome following pacemaker implantation

BACKGROUND

Pacemaker (PM) implantation may cause acute emotional distress leading to takotsubo syndrome (TTS). Frailty and cognitive impairment are known to influence outcomes after surgical procedures. It is unclear whether they may also predispose to TTS following PM implantation.

METHODS

We identified nine cases (81 ± 6 years) of TTS following PM implantation that took place between 2013 and 2017 in one high volume implantation center. TTS was diagnosed based on typical echocardiographic appearance with resolution over time and (in cases where deemed necessary) normal coronary angiography. The TTS cases were compared with 30 consecutive cases of PM implantation (75 ± 9 years), which were not complicated by TTS (control group). Frailty was assessed using retrospective Risk Analysis Index (RAI-A). Pacing parameters were analyzed during PM implantation and after 1 month.

RESULTS

Cognitive impairment was more prevalent (67% vs 10%, P = .0005), and RAI-A index was significantly higher in the TTS group compared to the control group (26 ± 13.7 vs 13.1 ± 9.8, P = .008). Perioperative right ventricular threshold was significantly higher in patients with TTS comparing to controls (0.99 ± 0.43 V vs 0.74 ± 0.20 V, P = .04). The magnitude of decrease in right ventricular threshold between implantation and 1 month follow-up was greater in TTS patients compared to controls (-0.41 ± 0.29 V vs -0.15 ± 0.38 V, P = .049).

CONCLUSIONS

TTS is a rare complication of PM implantation. Patients with cognitive impairment and frailty are at risk of TTS. Right ventricular pacing threshold is acutely affected by TTS and improves over time.

Delayed metabolic dysfunction in myocardium following exertional heat stroke in mice

KEY POINTS

Exposure to exertional heat stroke (EHS) is associated with increased risk of long-term cardiovascular disorders in humans. We demonstrate that in female mice, severe EHS results in metabolic changes in the myocardium, emerging only after 9-14 days. This was not observed in males that were symptom-limited at much lower exercise levels and heat loads compared to females. At 14 days of recovery in females, there were marked elevations in myocardial free fatty acids, ceramides and diacylglycerols, consistent with development of underlying cardiac abnormalities. Glycolysis shifted towards the pentose phosphate and glycerol-3-phosphate dehydrogenase pathways. There was evidence for oxidative stress, tissue injury and microscopic interstitial inflammation. The tricarboxylic acid cycle and nucleic acid metabolism pathways were also negatively affected. We conclude that exposure to EHS in female mice has the capacity to cause delayed metabolic disorders in the heart that could influence long-term health.

ABSTRACT

Exposure to exertional heat stroke (EHS) is associated with a higher risk of long-term cardiovascular disease in humans. Whether this is a cause-and-effect relationship remains unknown. We studied the potential of EHS to contribute to the development of a 'silent' form of cardiovascular disease using a preclinical mouse model of EHS. Plasma and ventricular myocardial samples were collected over 14 days of recovery. Male and female C57bl/6J mice underwent forced wheel running for 1.5-3 h in a 37.5°C/40% relative humidity until symptom limitation, characterized by CNS dysfunction. They reached peak core temperatures of 42.2 ± 0.3°C. Females ran ∼40% longer, reaching ∼51% greater heat load. Myocardial and plasma samples (n = 8 per group) were obtained between 30 min and 14 days of recovery, analysed using metabolomics/lipidomics platforms and compared to exercise controls. The immediate recovery period revealed an acute energy substrate crisis from which both sexes recovered within 24 h. However, at 9-14 days, the myocardium of female mice developed marked elevations in free fatty acids, ceramides and diacylglycerols. Glycolytic and tricarboxylic acid cycle metabolites revealed bottlenecks in substrate flow, with build-up of intermediate metabolites consistent with oxidative stress and damage. Males exhibited only late stage reductions in acylcarnitines and elevations in acetylcarnitine. Histopathology at 14 days showed interstitial inflammation in the female hearts only. The results demonstrate that the myocardium of female mice is vulnerable to a slowly emerging metabolic disorder following EHS that may harbinger long-term cardiovascular complications. Lack of similar findings in males may reflect their lower heat exposure.

Trigger factors in takotsubo syndrome - A systematic review of case reports

INTRODUCTION

Takotsubo syndrome is an acute heart failure syndrome often preceded by a trigger factor of physical or emotional origin, although the proportion is unclear. The aim of the present study was to determine how common different trigger factors are in takotsubo syndrome divided by sex and age in women.

MATERIAL AND METHODS

The study consisted of a systematic review of all available case reports in PubMed and Web of Science up to March 2018. Trigger factors were categorized into physical and emotional trigger factors.

RESULTS

Males had to a higher degree experienced a trigger factor (92.6%) compared to females (81.9%, p < .001). Physical trigger factors were most common (67.3%). Males had to a higher degree experienced a physical trigger factor (85.7%) compared to females (63.5%, p < .001). Females ≤50 years of age had to a higher degree experienced a trigger factor (90.8%) compared to females >50 years of age (79.2%, p < .001). Additionally, females ≤50 years of age had to a higher degree experienced a physical trigger factor (75.6%) compared to females >50 years of age (59.3%, p < .01).

CONCLUSION

A physical trigger factor is more common than an emotional trigger factor in takotsubo syndrome. Physical triggers includes drugs, surgery and central nervous system conditions. Furthermore, females ≤50 years of age and males more often have an evident trigger factor and it is more often physical, compared to the most common patient, a female >50 years of age.