Trigger-Associated Clinical Implications and Outcomes in Takotsubo Syndrome: Results From the Multicenter GEIST Registry.

Background Takotsubo syndrome is usually triggered by a stressful event. The type of trigger seems to influence the outcome and should therefore be considered separately. Methods and Results Patients included in the GEIST (German-Italian-Spanish Takotsubo) registry were categorized according to physical trigger (PT), emotional trigger (ET), and no trigger (NT) of Takotsubo syndrome. Clinical characteristics as well as outcome predictors were analyzed. Overall, 2482 patients were included. ET was detected in 910 patients (36.7%), PT in 885 patients (34.4%), and NT was observed in 717 patients (28.9%). Compared with patients with PT or NT, patients with ET were younger, less frequently men, and had a lower prevalence of comorbidities. Adverse in-hospital events (NT: 18.8% versus PT: 27.1% versus ET: 12.1%, P<0.001) and long-term mortality rates (NT: 14.4% versus PT: 21.6% versus ET: 8.5%, P<0.001) were significantly lower in patients with ET. Increasing age (P<0.001), male sex (P=0.007), diabetes (P<0.001), malignancy (P=0.002), and a neurological disorder (P<0.001) were associated with a higher risk of long-term mortality, while chest pain (P=0.035) and treatment with angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (P=0.027) were confirmed as independent predictors for a lower risk of long-term mortality. Conclusions Patients with ET have better clinical conditions and a lower mortality rate. Increasing age, male sex, malignancy, a neurological disorder, chest pain, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, and diabetes were confirmed as predictors of long-term mortality.

Measuring Water Distribution in the Heart: Preventing Edema Reduces Ischemia-Reperfusion Injury.

BACKGROUND: Edema is present in many heart diseases, and differentiation between intracellular (ICW) and extracellular (ECW) myocardial water compartments would be clinically relevant. In this work we developed a magnetic resonance imaging-based method to differentiate ICW and ECW and applied it to analyze ischemia-reperfusion-induced edema. METHODS AND RESULTS: Isolated rat hearts were perfused with gadolinium chelates as a marker of extracellular space. Total water content was measured by desiccation. Gadolinium quantification provided ECW, and ICW was calculated by subtraction of ECW from total water content. In separate experiments, T1, T2, diffusion-weighted imaging and proton-density parameters were measured in isolated saline-perfused hearts. In in-situ rat hearts, ECW and ICW were 79±10 mL and 257±8 mL of water per 100 g of dry tissue, respectively. After perfusion for 40 minutes, ECW increased by 92.4±3% without modifying ICW (-1±3%). Hyposmotic buffer (248 mOsm/L) increased ICW by 16.7±2%, while hyperosmotic perfusion (409 mOsm/L) reduced ICW by 26.5±3%. Preclinical imaging showed good correlation between T2 and diffusion-weighted imaging with ECW, and proton-density correlated with total water content. Ischemia-reperfusion resulted in marked myocardial edema at the expense of ECW, because of cellular membrane rupture. When cell death was prevented by blebbistatin, water content and distribution were similar to normoxic perfused hearts. Furthermore, attenuation of intracellular edema with hyperosmotic buffer reduced cell death. CONCLUSIONS: We devised a method to determine edema and tissue water distribution. This method allowed us to demonstrate a role of edema in reperfusion-induced cell death and could serve as a basis for the study of myocardial water distribution using magnetic resonance imaging.

Myocardial edema: a translational view.

Myocardial edema occurs in a large number of myocardial pathologies particularly during ischemia-reperfusion, and may contribute to cell dysfunction and death occurring in these conditions. Cardiomyocyte cell volume is tightly regulated by modifications in cytosolic osmolality. Changes in membrane water permeability through aquaporin and connexin hemichannels also contribute to cell volume changes while caveolae may be important in sensing cell volume changes sensing and associated signaling. Ischemia-reperfusion alters these mechanisms and increases microvascular permeability by endothelial hypercontracture-induced gap formation, endothelial cell death and basal membrane disruption. Detection of myocardial edema by MRI has many useful diagnostic applications in acute myocardial infarction and other conditions. However, discrimination between intra and extracellular myocardial edema is presently difficult at the bench and impossible at the bedside. Developing methods to differentiate intra from extracellular myocardial water should allow a better understanding of the mechanisms and consequences of myocardial edema and, as a consequence lead to new diagnostic and therapeutic applications.