Late coronary ischemıc syndromes assocıated wıth transcatheter aortıc valve ımplantatıon: A revıew of mechanıstıc and clınıcal aspects

In the past years, transcatheter aortic valve implantation (TAVI) has emerged as a promising option for the treatment of aortic valve pathologies particularly in the the presence of surgically high-risk situations. Importantly, a variety of specific procedural complications including acute coronary osteal occlusion, though very rare, has been reported in major clinical studies. However, little is known about the late impact of TAVI on coronary system at the macro and microvascular levels.

On the other hand, clinical studies as well as real life experiences have shown variable rates of acute coronary syndrome (ACS) readmissions among TAVI recipients in the short and long terms. Within this context, it may be suggested that even though late coronary ischemic events arising after TAVI, to some extent, appears to be spontaneous or attributable to certain stressors, TAVI may also have the potential to directly account for, accelerate or contribute to the evolution of these ischemic events on follow-up. Accordingly, the present review primarily focuses on potential association of TAVI with late coronary ischemic syndromes along with a particular emphasis on its mechanistic basis and clinical implications among TAVI recipients.

Left Ventricular Dysfunction in the Setting of Takotsubo Cardiomyopathy: A Review of Clinical Patterns and Practical Implications

Takotsubo cardiomyopathy (TTC) is primarily regarded as a form of acute and transient myocardial disease with a variety of characteristic wall-motion abnormalities. Importantly, a significant portion of TTC cases generally present with variable degrees of acute left ventricular (LV) dysfunction with or without clinical HF. On the other hand, LV dysfunction in the setting of TTC has been universally and exclusively considered as a synonym for systolic dysfunction, potentially overlooking other forms of myocardial pathologies, including transient diastolic dysfunction, in this setting. More interestingly, recent observations suggest that TTC, despite its macroscopic recovery, may not always manifest as a fully reversible phenomenon, suggesting persistence of microscopic changes at the cellular level to some degree. In clinical practice, these residual changes might largely account for the evolution of certain pathologies, including persistent diastolic dysfunction and subclinical LV dysfunction with variable symptomatology (particularly those arising during high levels of myocardial workload, including exercise, etc.) among TTC survivors. Within this context, the present review aims to highlight various clinical patterns and implications of LV dysfunction in the setting of TTC, and to provide basic information regarding morphological and mechanistic characteristics of wall-motion abnormalities in this setting.

Assessment of ventricular and left atrial mechanical functions, atrial electromechanical delay and P wave dispersion in patients with scleroderma

BACKGROUND

The aim of this study was to investigate ventricular functions and left atrial (LA) mechanical functions, atrial electromechanical coupling, and P wave dispersion in scleroderma patients.

METHODS

Twenty-six patients with scleroderma and twenty-four controls were included. Left and right ventricular (LV and RV) functions were evaluated using conventional echocardiography and tissue Doppler imaging (TDI). LA volumes were measured using the biplane area- -length method and LA mechanical function parameters were calculated. Inter-intraatrial electromechanical delays were measured by TDI. P wave dispersion was calculated by 12-lead electrocardiograms.

RESULTS

LV myocardial performance indices (MPI) and RV MPI were higher in patients with scleroderma (p = 0.000, p = 0.000, respectively) while LA passive emptying fraction was decreased and LA active emptying fraction was increased (p = 0.051, p = 0.000, respectively). P wave dispersion and inter-intraatrial electromechanical delay were significantly higher in patients with scleroderma (25 [10-60] vs 20 [0-30], p = 0.000, 16.50 [7.28-26.38] vs 9.44 [3.79-15.78] and 11.33 [4.88-16.06] vs 4.00 [0-12.90], p < 0.05, respectively). Interatrial electromechanical delay was negatively correlated with LV E wave, (p = 0.018). LV E wave was demonstrated to be a factor independent of the interatrial electromechanical delay (R² = = 0.270, b = -0.52, p = 0.013).

CONCLUSIONS

This study showed that in scleroderma patients, global functions of LV, RV and mechanical functions of LA were impaired, intra-interatrial electromechanical delays were prolonged and P wave dispersion was higher. LV E wave was demonstrated to be a factor that is independent of the interatrial electromechanical delay. Reduced LV E wave may also give additional information on the process of risk stratification of atrial fibrillation.

ST segment elevation following sinoventricular rhythm in a patient with diabetic ketoacidosis

Diabetic ketoacidosis is a major cause of morbidity and mortality in patients with insulin dependent diabetes. Myocardial infarction is an uncommon but well-recognised precipitating cause of diabetic ketoacidosis, accounting for 1% of cases. Many diabetic patients with ketoacidosis initially present with hyperkelamia, which may affect the electrocardiographic morphology. We present a patient with diabetic ketoacidosis and hyperkalemia, whose initial electrocardiogram showed a sinoventricular rhythm and subsequently pseudoinfarction pattern. (Cardiol J 2007; 14: 497-499).

Cannabis-induced coronary artery thrombosis and acute anterior myocardial infarction in a young man

Information concerning acute myocardial infarction after cannabis usage is limited and the actual mechanism of cannabis-induced myocardial infarction is not well known. In the report, we described a young man with an acute myocardial infarction and cannabis-induced coronary thrombosis.