Increased responsiveness of left ventricular apical myocardium to adrenergic stimuli

Characterization of Myocardial Microstructure and Function in an Experimental Model of Isolated Subendocardial Damage

Subendocardial damage is among the first cardiac manifestations of hypertension and is already present in asymptomatic disease states. Accordingly, markers of subendocardial impairment may facilitate early detection of cardiac damages and risk stratification under these conditions. This study aimed to investigate the impact of subendocardial damage on myocardial microstructure and function to elucidate early pathophysiologic processes and to identify corresponding diagnostic measures. Mice (n=38) were injected with isoproterenol to induce isolated subendocardial scarring or saline as corresponding control. Cardiac function and myocardial deformation were determined by high-frequency echocardiography. The cardiac stress response was assessed in a graded exercise test and during dobutamine stress echocardiography. Myocardial microstructure was studied ex vivo by 7 T diffusion tensor magnetic resonance imaging at a spatial resolution of 100×100×100 µm ³ . Results were correlated with histology and biomarker expression. Subendocardial fibrosis was accompanied by diastolic dysfunction, impaired longitudinal deformation (global peak longitudinal strain [LS]: -12.5±0.5% versus -15.6±0.5%; P<0.001) and elevated biomarker expression (ANP [atrial natriuretic peptide], Galectin-3, and ST2). Systolic function and cardiac stress response remained preserved. Diffusion tensor magnetic resonance imaging revealed a left-shift in helix angle towards lower values in isoproterenol-treated animals, which was mainly determined by subepicardial myofibers (mean helix angle: 2.2±0.8° versus 5.9±1.0°; P<0.01). Longitudinal strain and subepicardial helix angle were highly predictive for subendocardial fibrosis (sensitivity, 82%-92% and specificity, 89%-90%). The results indicate that circumscribed subendocardial damage alone can cause several hallmarks observed in cardiovascular high-risk patients. Microstructural remodeling under these conditions involves also remote regions, and corresponding changes in longitudinal strain and helix angle might serve as diagnostic markers.

New Approaches in the Management of Sudden Cardiac Death in Patients with Heart Failure-Targeting the Sympathetic Nervous System

Cardiovascular diseases (CVDs) have been considered the most predominant cause of death and one of the most critical public health issues worldwide. In the past two decades, cardiovascular (CV) mortality has declined in high-income countries owing to preventive measures that resulted in the reduced burden of coronary artery disease (CAD) and heart failure (HF). In spite of these promising results, CVDs are responsible for ~17 million deaths per year globally with ~25% of these attributable to sudden cardiac death (SCD). Pre-clinical data demonstrated that renal denervation (RDN) decreases sympathetic activation as evaluated by decreased renal catecholamine concentrations. RDN is successful in reducing ventricular arrhythmias (VAs) triggering and its outcome was not found inferior to metoprolol in rat myocardial infarction model. Registry clinical data also suggest an advantageous effect of RDN to prevent VAs in HF patients and electrical storm. An in-depth investigation of how RDN, a minimally invasive and safe method, reduces the burden of HF is urgently needed. Myocardial systolic dysfunction is correlated to neuro-hormonal overactivity as a compensatory mechanism to keep cardiac output in the face of declining cardiac function. Sympathetic nervous system (SNS) overactivity is supported by a rise in plasma noradrenaline (NA) and adrenaline levels, raised central sympathetic outflow, and increased organ-specific spillover of NA into plasma. Cardiac NA spillover in untreated HF individuals can reach ~50-fold higher levels compared to those of healthy individuals under maximal exercise conditions. Increased sympathetic outflow to the renal vascular bed can contribute to the anomalies of renal function commonly associated with HF and feed into a vicious cycle of elevated BP, the progression of renal disease and worsening HF. Increased sympathetic activity, amongst other factors, contribute to the progress of cardiac arrhythmias, which can lead to SCD due to sustained ventricular tachycardia. Targeted therapies to avoid these detrimental consequences comprise antiarrhythmic drugs, surgical resection, endocardial catheter ablation and use of the implantable electronic cardiac devices. Analogous NA agents have been reported for single photon-emission-computed-tomography (SPECT) scans usage, specially the 123I-metaiodobenzylguanidine (123I-MIBG). Currently, HF prognosis assessment has been improved by this tool. Nevertheless, this radiotracer is costly, which makes the use of this diagnostic method limited. Comparatively, positron-emission-tomography (PET) overshadows SPECT imaging, because of its increased spatial definition and broader reckonable methodologies. Numerous ANS radiotracers have been created for cardiac PET imaging. However, so far, [11C]-meta-hydroxyephedrine (HED) has been the most significant PET radiotracer used in the clinical scenario. Growing data has shown the usefulness of [11C]-HED in important clinical situations, such as predicting lethal arrhythmias, SCD, and all-cause of mortality in reduced ejection fraction HF patients. In this article, we discussed the role and relevance of novel tools targeting the SNS, such as the [11C]-HED PET cardiac imaging and RDN to manage patients under of SCD risk.

3T MRI evaluation of regional catecholamine-producing tumor-induced myocardial injury

OBJECTIVE

Regional differences in cardiac magnetic resonance, which can reveal catecholamine-induced myocardial injury in patients with pheochromocytoma, have not yet been assessed using 3T magnetic resonance imaging. We evaluated these differences using myocardial T1-mapping and strain analysis.

DESIGN AND METHODS

We retrospectively reviewed 16 patients newly diagnosed with catecholamine-producing tumors (CPT group) and 16 patients with essential hypertension (EH group), who underwent cardiac magnetic resonance imaging between May 2016 and March 2018. We acquired 3T magnetic resonance cine and native T1-mapping images and performed feature-tracking-based strain analysis in the former.

RESULTS

Global cardiac function, morphology, global strain and peak strain rate were similar, but end-diastolic wall thickness differed between groups (CPT vs EH: 10.5 ± 1.7 vs 12.6 ± 2.8 mm; P < 0.05). Basal, but not apical, circumferential strain was significantly higher in the CPT than the EH group (19.4 ± 3.2 vs 16.8 ± 3.6 %; P < 0.05). Native T1 values were significantly higher in CPT than in EH patients, in both the basal septum (1307 ± 48 vs 1241 ± 45 ms; P < 0.01) and the apical septum (1377 ± 59 vs 1265 ± 58 ms; P < 0.01) mid-walls. In the CPT, but not in the EH group, native T1 values in the apical wall were significantly higher than those in the basal wall (P < 0.01).

CONCLUSION

3T magnetic resonance-based T1-mapping can sensitively detect subclinical catecholamine-induced myocardial injury; the influence of catecholamines may be greater in the apical than in the basal wall.

"Takotsubo cardiomyopathy presenting with QT prolongation: an atypical presentation."

Takotasubo Cardiomyopathy (TCM), also known as broken heart syndrome, is a syndrome of transient and reversible cardiac dysfunction in the absence of obstructive coronary artery disease following an unpleasant emotional event. TCM commonly presents as chest pain mimicking acute coronary syndrome (ACS) in character. The most common electrocardiogram (EKG) findings associated with TCM are ST-segment elevation or T wave inversion. Herein, we present a case of TCM in an individual who presented with a sudden onset chest pressure following a stressful event. She was found to have QT interval prolongation on EKG and elevated troponins. Initially thought to have non-ST elevation myocardial infarction (NSTEMI). Cardiac catheterization did not reveal coronary artery disease. The ventriculography suggested apical ballooning and the diagnosis of TCM with atypical EKG presentation. Our case is unique as we describe an atypical electrocardiographic presentation of TCM. Our case emphasizes that physicians should refrain from prescribing QT-prolonging drugs to patients with TCM, to avert potential QT prolongation and progression to torsade de pointes (TDP).

A Case of Takotsubo Cardiomyopathy After Local Anesthetic and Epinephrine Infiltration

Takotsubo cardiomyopathy (TC) is a non-ischemic cardiomyopathy that is accompanied by sudden left ventricular myocardial stunning, dilation and dysfunction. It often results from severe emotional or physical stress. We present the case of a 41-year-old female patient who had general anesthesia induced uneventfully for an elective bladder sling procedure. After an intravaginal injection of local anesthesia (lidocaine 2%; epinephrine 1:100,000) just prior to the surgical incision, the patient had cardiovascular collapse for which cardiopulmonary resuscitation (CPR) was performed. The patient was eventually stabilized but transesophageal echocardiography showed impairment in cardiac motion and remarkably reduced ejection fraction. Troponin levels were elevated but coronary angiography was unremarkable. The ejection fraction returned to normal the next day. Local anesthetic with epinephrine administration can lead to TC, and with optimal management, long-term cardiac sequela can be avoided.

Left Ventricular Speckle Tracking-Derived Cardiac Strain and Cardiac Twist Mechanics in Athletes: A Systematic Review and Meta-Analysis of Controlled Studies

Background

The athlete’s heart is associated with physiological remodeling as a consequence of repetitive cardiac loading. The effect of exercise training on left ventricular (LV) cardiac strain and twist mechanics are equivocal, and no meta-analysis has been conducted to date.

Objective

The objective of this systematic review and meta-analysis was to review the literature pertaining to the effect of different forms of athletic training on cardiac strain and twist mechanics and determine the influence of traditional and contemporary sporting classifications on cardiac strain and twist mechanics.

Methods

We searched PubMed/MEDLINE, Web of Science, and ScienceDirect for controlled studies of aged-matched male participants aged 18–45 years that used two-dimensional (2D) speckle tracking with a defined athlete sporting discipline and a control group not engaged in training programs. Data were extracted independently by two reviewers. Random-effects meta-analyses, subgroup analyses, and meta-regressions were conducted.

Results

Our review included 13 studies with 945 participants (controls n = 355; athletes n = 590). Meta-analyses showed no athlete–control differences in LV strain or twist mechanics. However, moderator analyses showed greater LV twist in high-static low-dynamic athletes (d = –0.76, 95% confidence interval [CI] –1.32 to –0.20; p < 0.01) than in controls. Peak untwisting velocity (PUV) was greater in high-static low-dynamic athletes (d = –0.43, 95% CI –0.84 to –0.03; p < 0.05) but less than controls in high-static high-dynamic athletes (d = 0.79, 95% CI 0.002–1.58; p = 0.05). Elite endurance athletes had significantly less twist and apical rotation than controls (d = 0.68, 95% CI 0.19–1.16, p < 0.01; d = 0.64, 95% CI 0.27–1.00, p = 0.001, respectively) but no differences in basal rotation. Meta-regressions showed LV mass index was positively associated with global longitudinal (b = 0.01, 95% CI 0.002–0.02; p < 0.05), whereas systolic blood pressure was negatively associated with PUV (b = –0.06, 95% CI –0.13 to –0.001; p = 0.05).

Conclusion

Echocardiographic 2D speckle tracking can identify subtle physiological differences in adaptations to cardiac strain and twist mechanics between athletes and healthy controls. Differences in speckle tracking echocardiography-derived parameters can be identified using suitable sporting categorizations.

International Expert Consensus Document on Takotsubo Syndrome (Part I): Clinical Characteristics, Diagnostic Criteria, and Pathophysiology

Takotsubo syndrome (TTS) is a poorly recognized heart disease that was initially regarded as a benign condition. Recently, it has been shown that TTS may be associated with severe clinical complications including death and that its prevalence is probably underestimated. Since current guidelines on TTS are lacking, it appears timely and important to provide an expert consensus statement on TTS. The clinical expert consensus document part I summarizes the current state of knowledge on clinical presentation and characteristics of TTS and agrees on controversies surrounding TTS such as nomenclature, different TTS types, role of coronary artery disease, and etiology. This consensus also proposes new diagnostic criteria based on current knowledge to improve diagnostic accuracy.

Takotsubo cardiomyopathy following unintentionally large subcutaneous adrenaline injection: a case report

Introduction

Stress cardiomyopathy, also known as takotsubo syndrome, is characterized by transient left ventricular dysfunction not attributable to obstructive epicardial coronary artery disease. Several pathological mechanisms have been proposed, including multivessel coronary artery vasospasm, coronary microcirculatory dysfunction, and excess catecholamine secretion.

Case presentation

A 68-year-old male presented to our institution for elective surgical removal of a cutaneous basal cell carcinoma on the right side of his face. Within minutes following the administration of local anaesthesia, the patient developed severe hypertension, tachycardia, ST-segment elevation on the electrocardiogram, and non-sustained broad-complex tachycardia. Urgent cardiac catheterization revealed non-obstructive coronary artery disease and left ventriculography demonstrated apical hypokinesia and moderate systolic dysfunction consistent with the takotsubo syndrome. On review of the medications administered, it was noted that an unintentionally large dose of adrenaline (4mg) had been injected subcutaneously with lignocaine. He was monitored in the coronary care and recovered fully with supportive care only. Bisoprolol was initiated on day 1 post procedure. On follow-up one month later, his left ventricular function had normalized.

Discussion

Our case report provides direct evidence supporting the pathogenetic role of excess catecholamine secretion in the development of the takotsubo syndrome. A review of the literature reveals that both exogenous catecholamine administration (adrenaline injection in the context of anaphylaxis or infiltrative anaesthesia) and excess endogenous catecholamine (phaechromocytoma) secretion has been associated with the takotsubo syndrome. Local infiltrative anaesthesia with the addition of adrenaline is commonly used as a vasoconstrictor in a wide variety of surgical procedures. To reduce the risk of adverse events, the lowest effective concentration of adrenaline to provide pain control and vasoconstriction is recommended.

Takotsubo Syndrome: Clinical Features, Pathogenesis, Treatment, and Relationship with Cerebrovascular Diseases

PURPOSE OF REVIEW

This review paper aims to provide a complete and updated overview on the clinical and pathophysiological aspects of Takotsubo syndrome (TTS), including prognosis, therapy, and the association with cerebrovascular conditions.

RECENT FINDINGS

TTS is an increasingly recognized non-ischemic cardiomyopathy characterized by sudden, temporary weakening of the myocardium, of which the pathogenesis is unknown. Although pathogenesis of TTS remains unclear, a complex interaction between catecholamine-mediated stimulation, myocardial stunning, and subsequent stress-related myocardial dysfunction seems to be the main pathophysiological mechanism. Stroke is linked to TTS by a dual relationship since it may induce TTS by catecholamine release even if TTS itself also may be complicated by left ventricular thrombi leading to stroke. Given its possible complications, including the association with neurological diseases, both cardiologist and neurologists should be aware about TTS in order to diagnose it promptly and to initiate appropriate therapeutic measures.

Acute Myocardial Infarction and Stress Cardiomyopathy Are Not Mutually Exclusive

BACKGROUND

Stress cardiomyopathy is a transient cardiac syndrome characterized by reversible left ventricular systolic dysfunction precipitated by emotional or physiologic stress. The presence of obstructive coronary artery disease has been noted in stress cardiomyopathy.

METHODS

We describe 3 case reports of patients with acute coronary syndrome and transient wall motion abnormalities not usually seen in the distribution of coronary artery disease.

RESULTS

In these 3 cases of acute myocardial infarction, the distribution of the culprit coronary occlusion was not concordant with the territory of transient wall motion abnormality. Follow-up demonstrated resolution of the wall motion abnormalities without intervention in these territories.

CONCLUSION

We believe that the physiologic stress of the acute coronary syndrome may have precipitated the stress cardiomyopathy as presented by these patients. This is the first demonstration that stress cardiomyopathy may be precipitated by acute coronary syndrome.

Application of Speckle-Tracking Echocardiography in an Experimental Model of Isolated Subendocardial Damage

BACKGROUND

The subendocardium is highly vulnerable to damage and is thus affected even in subclinical disease stages. Therefore, methods reflecting subendocardial status are of great clinical relevance for the early detection of cardiac damage and the prevention of functional impairment. The aim of this study was to investigate the potential ability of myocardial strain parameters to evaluate changes within the subendocardium.

METHODS

Male 129/Sv mice were injected with isoproterenol (ISO; n = 32) to induce isolated subendocardial fibrotic lesions or saline as appropriate control (n = 15). Transthoracic echocardiography was performed using a 30-MHz linear-frequency transducer coupled to a high-resolution imaging system, and acquired images were analyzed for conventional and strain parameters. The degree of collagen content within the different cardiac layers was quantified by histologic analysis and serum levels of tissue inhibitor of metalloproteinase-1, a biomarker for fibrosis, were assessed.

RESULTS

ISO treatment induced a marked increase in subendocardial collagen content in response to cell loss (control vs ISO, 0.6 ± 0.3% vs 5.8 ± 0.9%; P < .001) and resulted in a moderate increase in left ventricular wall thickness with preserved systolic function. Global longitudinal peak strain (LS) and longitudinal strain rate were significantly decreased in ISO-treated animals (LS, -15.49% vs -11.49% [P = .001]; longitudinal strain rate, -4.81 vs -3.88 sec^-1 [P < .05]), whereas radial and circumferential strain values remained unchanged. Global LS was associated with subendocardial collagen content (r = 0.46, P = .01) and tissue inhibitor of metalloproteinase-1 serum level (r = 0.52, P < .05). Further statistical analyses identified global LS as a superior predictor for the presence of subendocardial fibrosis (sensitivity, 84%; specificity, 80%; cutoff value, -14.4%).

CONCLUSION

Assessment of LS may provide a noninvasive method for the detection of subendocardial damage and may consequently improve early diagnosis of cardiac diseases.

Heart-Brain Axis: Effects of Neurologic Injury on Cardiovascular Function

A complex interaction exists between the nervous and cardiovascular systems. A large network of cortical and subcortical brain regions control cardiovascular function via the sympathetic and parasympathetic outflow. A dysfunction in one system may lead to changes in the function of the other. The effects of cardiovascular disease on the nervous system have been widely studied; however, our understanding of the effects of neurological disorders on the cardiovascular system has only expanded in the past 2 decades. Various pathologies of the nervous system can lead to a wide range of alterations in function and structure of the cardiovascular system ranging from transient and benign electrographic changes to myocardial injury, cardiomyopathy, and even cardiac death. In this article, we first review the anatomy and physiology of the central and autonomic nervous systems in regard to control of the cardiovascular function. The effects of neurological injury on cardiac function and structure will be summarized, and finally, we review neurological disorders commonly associated with cardiovascular manifestations.

Recurrent Stress Cardiomyopathy During COPD Exacerbation: Are Beta-adrenergic Agonists Only to Blame?

Takotsubo cardiomyopathy (TCM) is a variant of stress-induced cardiomyopathy, characterized by transient left ventricular dysfunction that may be associated with emotional or physical triggers. We present the case of a 51-year-old Caucasian female with severe chronic obstructive pulmonary disease (COPD) who presented with syncope and was found to have her second lifetime episode of stress-induced cardiomyopathy. Eight months prior, she had been admitted with a COPD exacerbation and was found to have left ventricular (LV) dysfunction with ejection fraction (EF) of 22% attributed to TCM with subsequent normalization of her left ventricular function. Recurrence of stress-induced cardiomyopathy associated with COPD is a rare phenomenon and its presentation raises the possibility of a common underlying mechanism.

Takotsubo Cardiomyopathy Associated with Levothyroxine Over-replacement

Takotsubo cardiomyopathy (TC) is characterised by acute, transient left ventricular apical ballooning precipitated by emotional or physiologically stressful stimuli and has been previously associated with Grave’s disease based on a few clinical reports. More recently, the association with exogenous thyrotoxicosis and radioiodine-induced thyroiditis has also been described. Iatrogenic hyperthyroidism on patients on levothyroxine replacement therapy for hypothyroidism has not been reported as a cause of TC. The authors describe two female patients with TC associated with levothyroxine over-replacement. A 74-year-old and a 48-year-old female patient, medicated with levothyroxine (respectively, 2.27 μg/kg and 1.85 μg/kg) for autoimmune thyroiditis were admitted to our emergency room with precordial pain. The first had an electrocardiogram with ST-segment elevation in the anterior precordial leads, and the latter had sinus tachycardia with deep T-wave inversion and QT interval prolongation. Further investigation revealed a mild elevation of cardiac biomarker levels and severe apical hypokinesis, but no significant coronary lesions on catheterisation. The suppressed thyroid stimulating hormone (TSH) levels were verified in the cardiac intensive care unit: 0.21 and 0.07 mIU/l (0.35–5.50) respectively. Both patients showed improvement of the apical hypokinesis on the discharge echocardiogram and normalisation of cardiac biomarker levels. Levothyroxine dose was reduced. This case report focuses on the cardiovascular risks of thyrotoxicosis, emphasises the importance of correct dose adjustment on patients under levothyroxine replacement therapy and stresses that TSH should be determined in patients presenting with acute coronary syndrome and typical findings of TC.

The influence of adrenergic stimulation on sex differences in left ventricular twist mechanics

KEY POINTS

Sex differences in left ventricular (LV) mechanics occur during acute physiological challenges; however, it is unknown whether sex differences in LV mechanics are fundamentally regulated by differences in adrenergic control. Using two-dimensional echocardiography and speckle tracking analysis, this study compared LV mechanics in males and females matched for LV length during post-exercise ischaemia (PEI) and β₁ -adrenergic receptor blockade. Our data demonstrate that while basal rotation was increased in males, LV twist was not significantly different between the sexes during PEI. In contrast, during β₁ -adrenergic receptor blockade, LV apical rotation, twist and untwisting velocity were reduced in males compared to females. Significant relationships were observed between LV twist and LV internal diameter and sphericity index in females, but not males. These findings suggest that LV twist mechanics may be more sensitive to alterations in adrenergic stimulation in males, but more highly influenced by ventricular structure and geometry in females.

ABSTRACT

Sex differences in left ventricular (LV) mechanics exist at rest and during acute physiological stress. Differences in cardiac autonomic and adrenergic control may contribute to sex differences in LV mechanics and LV haemodynamics. Accordingly, this study aimed to investigate sex differences in LV mechanics with altered adrenergic stimulation achieved through post-handgrip-exercise ischaemia (PEI) and β₁ -adrenergic receptor (AR) blockade. Twenty males (23 ± 5 years) and 20 females (22 ± 3 years) were specifically matched for LV length (males: 8.5 ± 0.5 cm, females: 8.2 ± 0.6 cm, P = 0.163), and two-dimensional speckle-tracking echocardiography was used to assess LV structure and function at baseline, during PEI and following administration of 5 mg bisoprolol (β₁ -AR antagonist). During PEI, LV end-diastolic volume and stroke volume were increased in both groups (P < 0.001), as was end-systolic wall stress (P < 0.001). LV twist and apical rotation were not altered from baseline or different between the sexes; however, basal rotation increased in males (P = 0.035). During β₁ -AR blockade, LV volumes were unchanged but blood pressure and heart rate were reduced in both groups (P < 0.001). LV apical rotation (P = 0.036) and twist (P = 0.029) were reduced in males with β₁ -AR blockade but not females, resulting in lower apical rotation (males: 6.8 ± 2.1 deg, females: 8.8 ± 2.3 deg, P = 0.007) and twist (males: 8.6 ± 1.9 deg, females: 10.7 ± 2.8 deg, P = 0.008), and slower untwisting velocity (males: 68.2 ± 22.1 deg s^-1 , females: 82.0 ± 18.7 deg s^-1 , P = 0.046) compared to females. LV twist mechanics are reduced in males compared to females during reductions to adrenergic stimulation, providing preliminary evidence that LV twist mechanics may be more sensitive to adrenergic control in males than in females.

The Sympathetic Nervous System in the Pathogenesis of Takotsubo Syndrome

Takotsubo syndrome is a unique clinical condition of acute heart failure and reversible left ventricular dysfunction frequently precipitated by sudden emotional or physical stress. There is growing evidence that exaggerated sympathetic stimulation is central to the pathogenesis of this syndrome. Precisely how catecholamines mediate myocardial stunning in takotsubo syndrome remains incompletely understood; but possible mechanisms include epicardial spasm, microvascular dysfunction, direct adrenergic-receptor-mediated myocyte injury, and systemic vascular effects that alter ventricular-arterial coupling. Risk factors that increase sympathetic tone and/or catecholamine sensitivity may render individuals particularly susceptible to takotsubo syndrome during episodes of acute stress.

Left ventricular myocardial function assessed by three-dimensional speckle tracking echocardiography in Takotsubo cardiomyopathy

BACKGROUND

We aimed to investigate left ventricular (LV) functional recovery in Takotsubo cardiomyopathy (TC) using three-dimensional (3D) speckle tracking echocardiography.

METHODS

Twenty-one patients with TC who underwent routine and 3D echocardiography as well as electrocardiography were enrolled. 3D images were analyzed to measure 3D radial strain and area tracking (area change of each LV segment). Postsystolic shortening (PSS) or thickening (PST) was defined as a further shortening or thickening occurred after the end-systole. 3D echocardiography and ECG were repeated at 4 weeks and 6 months later.

RESULTS

Mean age was 70.9±11.1 years, and 18 (86%) patients were female. All patients presented classical type of TC with apical ballooning. LV ejection fraction (EF) improved from 49.9±7.2 to 64.9±6.0% (P<.001) at 4 weeks without segmental wall-motion abnormality. However, PSS or PST still existed in 43% of LV segments, and electrocardiographic abnormality was also observed in 51% at 4 weeks and disappeared at 6 months. Mean 3D radial strain decreased from baseline to 6 months at base (36.1±19.6 vs 28.0±12.6%, P=.04), whereas it increased at mid (16.2±7.2 vs 28.7±9.1%, P=.03) and the apex (8.0±4.4 vs 21.2±7.9%, P<.001). Mean area tracking increased from baseline to 6 months at mid and apex (-28.5±9.5 vs -44.5±9.6%, P<.001 for mid, and -24.2±13.0 vs -42.9±16.8%, P=.002 for the apex), while it did not change at base (-37.0±8.9 vs -41.9±9.6%, P=NS).

CONCLUSIONS

Patients with TC show abnormal wall motion during acute phase. Even after LV wall-motion recovery, subtle abnormalities of regional LV function appear to persist at 4 weeks followed by normalization at 6 months.

The Neurocardiogenic Spectrum in Subarachnoid Hemorrhage: A Case Report and Review of the Literature

A 36-year-old man was brought to our emergency department after successful resuscitation of out-of-hospital cardiac arrest with the whole spectrum of neurocardiogenic effects in subarachnoid hemorrhage: electrocardiographic changes, regional wall motion abnormalities, and elevations of cardiac enzymes. Coronary angiography revealed normal coronary arteries but showed the midventricular type of Takotsubo cardiomyopathy in the left ventriculography. Subsequently, cerebral computed tomography revealed diffuse subarachnoid hemorrhage and generalized cerebral edema with brain herniation. Brain death was diagnosed. This case highlights the possibility of an acute cerebral illness (especially subarachnoid hemorrhage) as an underlying cause of cardiac abnormalities mimicking myocardial ischemia.

Neurocardiac Injury After Cerebral and Subarachnoid Hemorrhages

Cerebrovascular events are associated with high mortality and morbidity rates. Neurocardiac injury after a subarachnoid hemorrhage and cerebral hemorrhage further worsen clinical outcomes. Excess catecholamine-induced cardiotoxicity is currently the most widely accepted pathophysiologic mechanism. Awareness of neurocardiac injury and the cardiac manifestations associated with it will allow for early diagnosis and appropriate management.

Left ventricular twist mechanics during incremental cycling and knee extension exercise in healthy men

Purpose

The objective of the present study was to investigate left ventricular (LV) twist mechanics in response to incremental cycling and isometric knee extension exercises.

Methods

Twenty-six healthy male participants (age = 30.42 ± 6.17 years) were used to study peak twist mechanics at rest and during incremental semi-supine cycling at 30 and 60% work rate maximum (W_max) and during short duration (15 s contractions) isometric knee extension at 40 and 75% maximum voluntary contraction (MVC), using two-dimensional speckle tracking echocardiography.

Results

Data presented as mean ± standard deviation or median (interquartile range). LV twist increased from rest to 30% W_max (13.21° ± 4.63° to 20.04° ± 4.76°, p < 0.001) then remained unchanged. LV systolic and diastolic twisting velocities progressively increased with exercise intensity during cycling from rest to 60% W_max (twisting, 88.21° ± 20.51° to 209.05° ± 34.56° s⁻¹, p < 0.0001; untwisting, −93.90 (29.62)° to −267.31 (104.30)° s⁻¹, p < 0.0001). During the knee extension exercise, LV twist remained unchanged with progressive intensity (rest 13.40° ± 4.80° to 75% MVC 16.77° ± 5.54°, p > 0.05), whilst twisting velocity increased (rest 89.15° ± 21.77° s⁻¹ to 75% MVC 124.32° ± 34.89° s⁻¹, p < 0.01). Untwisting velocity remained unchanged from rest [−90.60 (27.19)° s⁻¹] to 40% MVC (p > 0.05) then increased from 40 to 75% MVC [−98.44 (43.54)° s⁻¹ to −138.42 (73.29)° s⁻¹, p < 0.01]. Apical rotations and rotational velocities were greater than basal during all conditions and intensities (all p < 0.01).

Conclusion

Cycling increased LV twist to 30% W_max which then remained unchanged thereafter, whereas twisting velocities showed further increases to greater intensities. A novel finding is that LV twist was unaffected by incremental knee extension, yet systolic and diastolic twisting velocities augmented with isometric exercise.

Comparison and outcome analysis of patients with apical and non-apical takotsubo cardiomyopathy

BACKGROUND

Takotsubo cardiomyopathy (TTC) is a relevant differential diagnosis in patients presenting with signs of an acute coronary syndrome. Although recent literature has highlighted some salient features of this disorder, there has been little information elucidating the differences in clinical features, electrocardiographic findings, echocardiographic data and TTC-related complications associated with the different variants of TTC.

METHODS AND RESULTS

Our institutional database constituted a collective of 114 patients diagnosed with TTC between 2003 and 2015 and these patients were subsequently divided into two groups based on the presence (n = 82, 72%) or absence (n = 32, 28%) of the apical form of TTC. The protocol for our proposed study was approved by the Ethics Committee of the University Medical Centre in Mannheim. It was noticed that the patients presenting with the apical form of TTC belonged to an older age group as compared to those presenting with the non-apical form (61.1 ± 8.9 years vs. 69.5 ± 11.2; P  < 0.01). The QTc interval prolongation at index-event was observed to be quantifiably greater in the 'apical variant' patients group (484.8 ± 57 ms vs. 464 ± 34.1 ms; P = 0.06). With respect to cardiovascular risk factors, patients with arterial hypertension did have a higher predilection to present with the apical form (63.4% vs. 43.7%; P = 0.06), however, the impact of smoking was less pronounced in this patient group (24.4% vs. 50%, P = 0.01). Furthermore, our study highlighted a significant impact on ejection fraction (EF), with a compromised left ventricular function (36 ± 9% vs. 42.4 ± 9.7%, P < 0.01) and greater involvement of the right ventricle in the apical variant patients group (23% vs. 3%, P = 0.04). Patients with the apical form also showed a greater tendency to develop TTC-related complications such as cardiogenic shock and required longer monitoring and care in comparison.

CONCLUSIONS

The apical and non-apical variants of TTC are manifestations of the same syndrome. They differ significantly, however, in their clinical presentation, related complications and prognosis.

Neurogenic stunned myocardium in subarachnoid hemorrhage

"Stunned myocardium," characterized by reversible left ventricular dysfunction, was first described via animal models using transient coronary artery occlusion. However, this phenomenon has also been noted with neurologic pathologies and collectively been labeled "neurogenic stunned myocardium" (NSM). Neurogenic stunned myocardium resulting from subarachnoid hemorrhage (SAH) is a challenging pathology due to its diagnostic uncertainty. Traditional diagnostic criteria for NSM after SAH focus on electrocardiographic and echocardiographic abnormalities and troponemia. However, tremendous heterogeneity still exists. Traditional pathophysiological mechanisms for NSM encompassed hypothalamic and myocardial perivascular lesions. More recently, research on pathophysiology has centered on myocardial microvascular dysfunction and genetic polymorphisms. Catecholamine surging as a mechanism has also gained attention with particular focus placed on the role of adrenergic blockade in both the prehospital and acute settings. Management remains largely supportive with case reports acknowledging the utility of inotropes such as dobutamine and milrinone and intra-aortic balloon pump when NSM is accompanied by cardiogenic shock. Neurogenic stunned myocardium that follows SAH can result in many complications such as arrhythmias, pulmonary edema, and prolonged intubation, which can negatively impact long-term recovery from SAH and increase morbidity and mortality. This necessitates the need to accurately diagnose and treat NSM.

Recurrent takotsubo with prolonged QT and torsade de pointes and left ventricular thrombus

Takotsubo cardiomyopathy, also known as “takotsubo syndrome,” refers to transient apical ballooning syndrome, stress cardiomyopathy, or broken heart syndrome and is a recently recognized syndrome typically characterized by transient and reversible left ventricular dysfunction that develops in the setting of acute severe emotional or physical stress. Increased catecholamine levels have been proposed to play a central role in the pathogenesis of the disease, although the specific pathophysiology of this condition remains to be fully determined. At present, there have been very few reports of recurrent takotsubo cardiomyopathy. In this case report, we present a patient with multiple recurrences of takotsubo syndrome triggered by severe emotional stress that presented with recurrent loss of consciousness, QT prolongation, and polymorphic ventricular tachycardia (torsade de pointes) and left ventricular apical thrombus.

Stress cardiomyopathy: Is it limited to Takotsubo syndrome? Problems of definition

In 2006, Takotsubo syndrome (TTC) was described as a distinct type of stress-induced cardiomyopathy (stress cardiomyopathy). However, when thinking about Takotsubo cardiomyopathy from the viewpoints of the AHA and ESC classifications, 2 possible problems may arise. The first potential problem is that a forecast of disease outcome is lacking in the ESC classification, whereas the AHA only states that 'outcome is favorable with appropriate medical therapy'. However, based on the literature data, one can make a general conclusion that occurrence of myocardial lesions in TTC (i.e., myocardial fibrosis and contraction-band necrosis) causes the same effects as in other diseases with similar levels of myocardial damage and should not be considered to have a lesser impact on mortality. To summarise, TTC can cause not only severe complications such as pulmonary oedema, cardiogenic shock, and dangerous ventricular arrhythmias, but also damage to the myocardium, which can result in the development of potentially fatal conditions even after the disappearance of LV apical ballooning. The second potential problem arises from the definition of TTC as a stress cardiomyopathy in the AHA classification. In fact, the main factors leading to TTC are stress and microvascular anginas, since, as has been already discussed, coronary spasm can cause myocardium stunning, resulting in persistent apical ballooning. Thus, based on this review, 3 distinct types of stress cardiomyopathies exist (variant angina, microvascular angina, and TTC), with poor prognosis. Adding these diseases to the classification of cardiomyopathies will facilitate diagnosis and preventive prolonged treatment, which should include intensive anti-stress therapy.

Clinical and Echocardiographic Characteristics of Acute Cardiac Dysfunction Associated With Acute Brain Hemorrhage - Difference From Takotsubo Cardiomyopathy

BACKGROUND

Cardiac dysfunction (CD) associated with brain hemorrhage is similar to that with takotsubo cardiomyopathy but still not well understood. We aimed to investigate the clinical and echocardiographic findings of acute CD (ACD) related to brain hemorrhage.

METHODS AND RESULTS

Between 2013 and 2014, consecutive patients diagnosed with spontaneous and traumatic brain hemorrhage were prospectively enrolled. Electrocardiography, cardiac enzymes, and echocardiography were performed. Left ventricular (LV) systolic dysfunction on echocardiography was defined as ACD related to brain hemorrhage when all the following conditions were satisfied: abnormal ECG and cardiac troponin level, LV wall motion abnormality or decreased LV systolic function on echocardiography, and no previous history of cardiac disease. Otherwise, LV dysfunction was considered to be other CD unrelated to brain hemorrhage. In a total of 208 patients, 15 (7.2%) showed ACD. Of them, 8 patients were men and 8 showed apex-sparing LV hypokinesia and 9 died in hospital. Other cardiac abnormalities observed in the study patients were NT-proBNP elevation (n=123), QT interval prolongation (n=95), LV hypertrophy (n=89), and troponin I elevation (n=47). There were 36 in-hospital deaths (17.3%). Glasgow coma score and ACD were independently associated with in-hospital death.

CONCLUSIONS

ACD was observed in patients with various brain hemorrhages. Unlike takotsubo cardiomyopathy, high proportions of male sex, apex-sparing LV dysfunction, and in-hospital death were observed for ACD associated with brain hemorrhage. (Circ J 2016; 80: 2026-2032).

Characteristics and mid-term follow-up of a single-center population affected by Tako-Tsubo cardiomyopathy

INTRODUCTION

Tako-Tsubo cardiomyopathy (TTC) is an acute cardiomyopathy mimicking acute myocardial infarction. The aim of our study was to define clinical and instrumental features of an Italian population of patients with TTC and to report their short and mid-term outcome.

METHODS

We retrospectively evaluated 42 patients admitted to our Department with diagnosis of TTC (100% women, age 67 ± 11 years) using Mayo Clinic-modified criteria. In this population, we analyzed the stressful event (if present), the clinical presentation, the ECG and echocardiogram at admission and the markers of myocardial cytonecrosis, such as troponin I, at admission and during the hospitalization. All the patients have been clinically evaluated after 6 months and 1 year of follow-up.

RESULTS

In this population, a stressful event before TTC has been detected in 59% of patients. The most common clinical presentation was chest pain (81%) and the major sign was dyspnea (17%). ECG showed negative T waves and ST elevation, respectively, in 45 and 38%. Only 10% had a ST depression and 7% developed a newly acquired complete left bundle branch block. All of these abnormalities disappeared within 1.8 ± 0.9 days. The mean ejection fraction at admission was 35 ± 7% associated with apical (40%), mid-apical (56%) and mid-ventricular (4%) wall motion abnormalities. The recovery of these abnormalities occurred within 10 ± 3 days. At 6-month and 1-year follow-up, no patients had TTC recurrence, and 10 patients at 6 months and 20 patients at 1 year were re-hospitalized for a non-cardiac cause.

CONCLUSION

Our data describe the characteristics of TTC in a small Italian population, which are similarly described in Japanese and North American people. TTC was related to a very low mortality, both in the short and mid term, but the risk of acute heart failure in the acute phase could not be neglected.

Regenerative Medicine: Potential Mechanisms of Cardiac Recovery in Takotsubo Cardiomyopathy

OPINION STATEMENT

Takotsubo cardiomyopathy is an increasingly reported cause of acute chest pain and acute heart failure and is often associated with significant hemodynamic compromise. The illness is remarkable for the reversibility in systolic dysfunction seen in the disease course. While the pathophysiology of takotsubo syndrome is not completely elucidated, research suggests the presence of a cytoprotective process that allows the myocardium to recover following the inciting insult. Here, we summarize molecular and histologic studies exploring the response to injury in takotsubo disease and provide some discussion on how they may contribute to further investigations in cardiac recovery and regeneration.

Takotsubo cardiomyopathy in a patient with pituitary adenoma and secondary adrenal insufficiency

We describe a case of Takotsubo cardiomyopathy in a case of pituitary macroadenoma in acute adrenal crisis. A 48-year-old man presented with acute onset altered sensorium, vomiting, and gasping. On admission, he was unresponsive and hemodynamically unstable. He was intubated and ventilated and resuscitated with fluids and inotropes. The biochemical evaluation revealed hyponatremia, hyperkalemia, and hypocortisolism. Hyponatremia was corrected with 3% hypertonic saline. Contrast enhanced computed tomography (CT) scan of the brain revealed a sellar-suprasellar mass with hypothalamic extension with no evidence of pituitary apoplexy. A diagnosis of invasive pituitary adenoma with the Addisonian crisis was made and steroid replacement was initiated. Despite volume resuscitation, he had persistent refractory hypotension, recurrent ventricular tachycardia, and metabolic acidosis. Electrocardiogram (ECG) showed ST elevation and T-wave inversion in lateral leads; cardiac-enzymes were increased suggestive of acute coronary syndrome. Transthoracic echocardiography showed severe regional wall motion abnormalities (RWMAs) involving left anterior descending territory and low ejection fraction (EF). Coronary angiogram revealed normal coronaries, apical ballooning, and severe left ventricular dysfunction, consistent with a diagnosis of Takotsubo's cardiomyopathy. Patient was managed with angiotensin-converting enzyme inhibitors and B-blockers. He improved over few days and recovered completely. At discharge, ECG changes and RWMA resolved and EF normalized to 56%. In patients with Addisonian Crisis with persistent hypotension refractory to optimal resuscitation, possibility of Takotsubo's cardiomyopathy should be considered. Early recognition of association of Takotsubos cardiomyopathy in neurological conditions, prompt resuscitation, and supportive care are essential to ensure favorable outcomes in this potentially lethal condition.

Takotsubo Cardiomyopathy in an Adult Woman With Repaired Tetralogy of Fallot

Takotsubo cardiomyopathy is a reversible form of cardiomyopathy rarely reported in the adult congenital patient. We describe a case of a 49-year-old woman with repaired tetralogy of Fallot who presented with acute dyspnea. A 12-lead electrocardiogram revealed diffuse anterolateral T-wave inversion suggestive of myocardial ischemia. Cardiac catheterization was performed, demonstrating angiographically normal coronary arteries. A cardiovascular magnetic resonance examination showed apical akinesis with associated myocardial edema, but no myocardial damage on late gadolinium enhancement imaging, which is a characteristic of Takotsubo cardiomyopathy. The patient was treated medically. A follow-up echocardiogram demonstrated normalization of left ventricular systolic function and apical wall motion abnormalities.

Left ventricular outflow track obstruction and mitral valve regurgitation in a patient with takotsubo cardiomyopathy

Introduction

Takotsubo cardiomyopathy (TCM) can be complicated by left ventricular outflow tract (LVOT) obstruction and severe acute mitral regurgitation (MR), leading to hemodynamic instability in an otherwise benign disorder. Despite the severity of these complications, there is a paucity of literature on the matter. Because up to 20–25% of TCM patients develop LVOT obstruction and/or MR, it is important to recognize the clinical manifestations of these complications and to adhere to specific management in order to reduce patient morbidity and mortality. We report the clinical history, imaging, treatment strategy, and clinical outcome of a patient with TCM that was complicated with severe MR and LVOT obstruction. We then discuss the pathophysiology, characteristic imaging, key clinical features, and current treatment strategy for this unique patient population.

Case report

A postmenopausal woman with no clear risk factor for coronary artery disease (CAD) presented to the emergency department with chest pain after an episode of mental/physical stress. Physical examination revealed MR, mild hypotension, and pulmonary vascular congestion. Her troponins were mildly elevated. Cardiac catheterization excluded obstructive CAD, but revealed severe apical hypokinesia and ballooning. Notably, multiple diagnostic tests revealed the presence of severe acute MR and LVOT obstruction. The patient was diagnosed with TCM complicated by underlying MR and LVOT obstruction, and mild hemodynamic instability. The mechanism of her LVOT and MR was attributed to systolic anterior motion of the mitral valve (SAM), which the transesophageal echocardiogram clearly showed during workup. She was treated with beta-blocker, aspirin, and ACE-I with good outcome. Nitroglycerin and inotropes were discontinued and further avoided.

Conclusions

Our case illustrated LVOT obstruction and MR associated with underlying SAM in a patient with TCM. LVOT obstruction and MR are severe complications of TCM and may result in heart failure and/or pulmonary edema. Timely and accurate identification of these complications is critical to achieve optimal clinical outcomes in patients with TCM.

Chronic stress impacts the cardiovascular system: animal models and clinical outcomes

Psychological stresses are associated with cardiovascular diseases to the extent that cardiovascular diseases are among the most important group of psychosomatic diseases. The longstanding association between stress and cardiovascular disease exists despite a large ambiguity about the underlying mechanisms. An array of possibilities have been proposed including overactivity of the autonomic nervous system and humoral changes, which then converge on endothelial dysfunction that initiates unwanted cardiovascular consequences. We review some of the features of the two most important stress-activated systems, i.e., the humoral and nervous systems, and focus on alterations in endothelial function that could ensue as a result of these changes. Cardiac and hematologic consequences of stress are also addressed briefly. It is likely that activation of the inflammatory cascade in association with oxidative imbalance represents key pathophysiological components of stress-induced cardiovascular changes. We also review some of the commonly used animal models of stress and discuss the cardiovascular outcomes reported in these models of stress. The unique ability of animals for adaptation under stressful conditions lessens the extrapolation of laboratory findings to conditions of human stress. An animal model of unpredictable chronic stress, which applies various stress modules in a random fashion, might be a useful solution to this predicament. The use of stress markers as indicators of stress intensity is also discussed in various models of animal stress and in clinical studies.

Reversible Cardiomyopathies

Cardiomyopathies (CMs) have many etiological factors that can result in severe structural and functional dysregulation. Fortunately, there are several potentially reversible CMs that are known to improve when the root etiological factor is addressed. In this article, we discuss several of these reversible CMs, including tachycardia-induced, peripartum, inflammatory, hyperthyroidism, Takotsubo, and chronic illness-induced CMs. Our discussion also includes a review on their respective pathophysiology, as well as possible management solutions.

Novel echocardiographic techniques for the evaluation of athletes' heart: A focus on speckle-tracking echocardiography

BACKGROUND

The development and rapid dissemination of two-dimensional echocardiography led to important further advances in our understanding of athletes' heart that has been the subject of several echocardiographic studies involving many thousands of athletes. The description of ventricular chamber enlargement, myocardial hypertrophy and atrial dilatation has led to a more comprehensive understanding of cardiac adaptation to exercise conditioning. Most recently, advanced echocardiographic techniques have begun to clarify significant functional adaptations of the myocardium that accompany previously reported morphological features of athletes' heart. In particular, speckle-tracking echocardiography (STE) has recently provided further insights into the characterisation of myocardial properties.

DISCUSSION

STE is a relatively new, largely angle-independent, non-invasive imaging technique that allows for an objective and quantitative evaluation of global and regional myocardial function. STE has enhanced our understanding of athletes' heart through a comprehensive characterisation of biventricular and biatrial function, providing novel insights into the investigation of physiological adaptation of the heart to exercise conditioning. These peculiarities can provide further useful data to distinguish between athletes' heart and cardiomyopathies. Furthermore, STE represents a promising tool to address new concerns on right ventricular function and to increase understanding of the complexity of the non-systemic circulation, especially in the athletic population.

CONCLUSION

This review article analyses new data on cardiac function in athletes by novel echocardiographic techniques with a particular attention to the application of STE to characterise biventricular and biatrial function in athletes.

Focal mid-ventricular anterior ballooning: An unusual pattern of Takotsubo cardiomyopathy

Takotsubo cardiomyopathy (TC) or left ventricular apical ballooning syndrome is typically characterized by reversible systolic dysfunction of the apical- and mid-segments of the left ventricle. Symptoms are precipitated by intense emotional or physical stress, in the absence of obstructive coronary artery lesions. The most common presentation of TC is a transient left ventricular apical ballooning. However, recent case reports have described various patterns of TC associated with distinct regional left ventricular wall motion abnormalities. One of very rare these variants, referred to as a "mid-ventricular" type, is characterized by akinesis with or without ballooning of the mid-ventricular segment, together with a hyperdynamic base and apex. Using left ventriculography we describe an atypical form of TC with transient, focal mid-ventricular ballooning of the anterior segment, followed by complete resolution of ballooning, as observed by cardiac magnetic resonance (CMR) imaging.