Controlling Hypertension and Stroke Prevention – From Guideline to Clinical Practice

Hypertension is the most important of the prevalent and modifiable risk factors for stroke. Based on evidence, blood pressure (BP) lowering is recommended in guidelines for the prevention of stroke. However, there are still some uncertainties in the guidelines for controlling BP and preventing stroke in patients with previous cerebrovascular events, such as the goal BP, who to treat and which class of BP-lowering drugs to use. This article discusses these questions by reviewing guidelines and corresponding clinical trials, with the aim of reducing the gap between guidelines and clinical practice.

Electrocardiogram Recognition and Ablation of Atrial Tachycardia

Focal atrial tachycardia (AT) is a relatively uncommon cause of supraventricular tachycardia, but when present is frequently difficult to treat medically. Atrial tachycardias tend to originate from anatomically determined atrial sites. The P-wave morphology on surface electrocardiogram (ECG) together with more sophisticated contemporary mapping techniques facilitates precise localisation and ablation of these ectopic foci. Catheter ablation of focal AT is associated with high long-term success and may be viewed as a primary treatment strategy in symptomatic patients.

Identification of High-risk Patients for Implantable Cardioverter–Defibrillator Therapy in Asia

Sudden cardiac death (SCD) is a serious medical problem worldwide. Multiple landmark studies have demonstrated the benefit of implantable cardioverter–defibrillator (ICD) therapy in preventing SCD in at-risk patients. Although the data available in Asia are limited, the disease pattern seems to be different from that in the western world. The Asian population seems to have a lower incidence of SCD. Coronary heart disease, which is the major underlying cause of SCD in the west, may play a less important role in Asian countries. In addition, non-structural heart disease seems to be a more prevalent cause of SCD in Asia. It is thus questionable whether the results of ICD trials can be applied directly to Asian countries, as most of these trials seldom recruited Asian patients. This article will review SCD in Asia, focusing on the epidemiology and risk factors for SCD in Asia and highlighting some unique features that may be different from those seen in the western world.

Recent Advances in Pacing and Defibrillation

Cardiac pacemakers have been the standard therapy for patients with bradyarrhythmias for several decades. The pacing lead is an integral part of the system, serving as a conduit for the delivery of energy pulses to stimulate the myocardium. However, it is also the Achilles’ heel of pacemakers, being the direct cause of most device complications both acutely during implant and chronically years afterwards. Leadless pacing with ultrasound-mediated energy has been demonstrated in animals and humans to be safe and feasible in acute studies. Implantable defibrillators revolutionised the treatment and prevention of sudden cardiac death. Subcutaneous implantable defibrillators have been under development for more than 10 years. A permanent implantable system has been shown to be feasible in treating induced and spontaneous ventricular tachyarrhythmias. These developments and recent advances in pacing and defibrillation will arouse further interest in the research and development of leadless cardiac implantable electronic devices.

Diagnosis and Ablation of Fascicular Tachycardia

Verapamil-sensitive fascicular ventricular tachycardia (VT) is the most common form of idiopathic left VT. According to the QRS morphology and the successful ablation site, left fascicular VT can be classified into three subgroups: left posterior fascicular VT, whose QRS morphology shows right bundle branch block (RBBB) configuration and superior axis (common form); left anterior fascicular VT, whose QRS morphology shows RBBB configuration and right-axis deviation (uncommon form), and upper septal fascicular VT, whose QRS morphology shows narrow QRS configuration and normal or right-axis deviation (rare form). Posterior and anterior fascicular VT can be successfully ablated at the posterior or anterior mid-septum with a diastolic Purkinje potential during VT or at the VT exit site with a fused pre-systolic Purkinje potential. Upper septal fascicular VT can also be ablated at the site with diastolic Purkinje potential at the upper septum. Recognition of the heterogeneity of this VT and its unique characteristics should facilitate appropriate diagnosis and therapy.

Clinical and Diagnostic Aspects of Takotsubo Cardiomyopathy

In recent years, the number of documented cases of takotsubo cardiomyopathy, which occurs mainly in elderly women, has been increasing all over the world. Takotsubo cardiomyopathy presents quite similar symptoms to acute anterior myocardial infarction, but with normal coronary arteries and left ventricular apical ballooning. Takotsubo cardiomyopathy has been recognised as a source of acute heart failure, lethal ventricular arrhythmia and ventricular rupture. The onset mechanism of this syndrome is still a matter of debate. In this article, we summarise previous studies and future issues regarding takotsubo cardiomyopathy.

Conceptual Framework of Collateral-promoting Therapy for Coronary Artery Disease

Human coronary collateral circulation (CCC) serves as an alternative blood-conveying circuit to the ischaemic myocardium. Functional potentiation of CCC is considered as a therapeutic approach in patients with intractable angina for whom revascularisation procedures such as percutaneous coronary intervention and coronary artery bypass graft surgery are not indicated. Augmentation of CCC is established by collateral recruitment and growth. Nitrates and sarpogrelate are representative drugs that enhance collateral recruitment. Exercise, enhanced external counterpulsation and whole-body periodic acceleration accelerate and potentiate collateral growth via increased mechanical stress at pre-existent collateral arterioles. Granulocyte macrophage colony-stimulating factor and heparin favourably modulate the cascade of coronary collateral growth. Further experimental and clinical studies will be needed to create more sophisticated coronary collateral-promoting therapies.

Controlling Blood Pressure without Drugs – Developing New Strategies

Non-optimal blood pressure is the leading cause of cardiovascular-related death worldwide, and each year is responsible for seven million deaths. Current therapeutic strategies for hypertension are mainly based on lifestyle interventions and pharmacological approaches, but rates of blood pressure control remain unsatisfactory and additional options are required. In this context, novel device-based approaches specifically targeting the sympathetic nervous system as a major player in blood pressure control have recently been tested clinically with promising results. Device-based approaches may provide additional and more effective treatment of hypertension and its adverse consequences in the future.