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The diagnosis of an idiopathic RVOT-VT is made by exclusion of ARVC or any other structural heart disease. If there are no signs of RV myocardial changes, such as dilatation, dyskinesia, hypokinesia, or aneurysms and wall thickening, and there are no electrocardiographic signs of ARVC, the patient most likely has an idiopathic RVOT-VT. However, especially in families with a history of sudden death, close follow-up may be useful. When enough minor or major criteria are met, the patient should be risk-stratified and treatment options should be tailored to the individual, taking into consideration the risks and benefits. In some younger patients with, e.g. syncope and one other minor criterion and RVOT-VT, this decision is often very difficult and will probably remain difficult. Genetic testing should be performed in all patients with a family history in order to detect relatives at risk.

Based on these data, we can conclude that although aldosterone antagonists are non-antiarrhythmic drugs, they have a significant preventive effect on SCD. The available data have focused particularly on the patients with low ejection fraction and congestive heart failure. New studies are needed to expand the indications to use aldosterone antagonists to prevent SCD. Potential mechanisms by which these drugs prevent SCD include prevention of aldosterone-induced cardiac and arterial fibrosis, improvement in arterial compliance, reduction of the adverse effects of aldosterone on cardiac remodelling, improvement of endothelial function and NO activity, improvement in the autonomic nervous system function via a reduction in sympathetic nervous system tonus, improvement in HRV and baroreflex sensitivity, and an increase in myocardial norepinephrine uptake By decreasing urinary excretion of potassium and magnesium, aldosterone antagonists also aid in protecting against life-threatening ventricular arryhthmias.

MRI and MDCT can play important roles in understanding the underlying causes of atrial and ventricular arrhythmias. In addition, they are becoming more and more often incorporated into the development of new interventional therapies for these clinical conditions.

TEE is a useful tool to investigate patients undergoing ablation therapy of atrial fibrillation. The technique provides important information about the presence of thrombus and SEC in the left atrium and LAa, and about minor IAS abnormalities, which seem to occur more frequently than in the normal population. Such information is necessary for planning the approach to the PV by catheters that must cross the septum and the atrial cavity.

After ablation, TEE can be used to monitor possible minor complications, such as a residual IAS shunt or pericardial effusion. It also allows the detection of PV stenosis, a rare but dreaded complication of PVAI. A control TEE examination 3 months after the ablation procedure is probably adequate for this purpose.

The low risk of ICD implantation and the evidence that these devices successfully terminate life-threatening ventricular tachyarrhythmias have prompted the use of ICDs in the primary prevention of sudden death in specific clinical conditions associated with a substantially increased risk of sudden arrhythmic death, including non-ischaemic cardiomyopathy. Despite continuing price reductions, cost is likely to remain a major determinant of the complete acceptance and implementation of ICD therapy. Therefore, the problem of how broadened evidence-based indications for implantation can be translated into the ‘real world’ remains to be addressed and resolved, considering currently available economic resources. Cost-effectiveness analysis provides the most appropriate tool for weighing costs against benefits for both ICD and CRT-D and should be directed towards specifically defined subsets of patients, including those with non-ischaemic cardiomyopathy.

There is no question but that early defibrillation will save lives. Despite the existence of well-developed emergency medical services with rapid-response advanced life support capabilities, survival rates following out-of-hospital VF have remained low. Generally, these poor resuscitation rates are attributed to delays in the performance of basic cardiopulmonary resuscitation by bystanders or delays in defibrillation.

The appropriateness of having defibrillators available in public places such as schools, apartment buildings, and offices is becoming clear. The PAD trial has demonstrated that training and equipping volunteers to attempt early defibrillation within a structured response system can increase the number of survivors to hospital discharge after out-of-hospital cardiac arrest in public locations. In airports, aeroplanes, casinos, and other high-risk locations, public use of external defibrillators should be strongly supported. In addition, efforts by private individuals to obtain defibrillators for homes and businesses seem justified. Dual EMS systems incorporating defibrillators have also shown good improvements in outcomes compared to EMS alone. In our opinion, public access defibrillation is here to stay.

Although final results are not yet available, it is interesting to note that patients who had complete disconnection of the superior vena cava have had a good initial follow-up. However, these preliminary results must be confirmed by studies that include a larger number of patients and a longer follow-up time.

Based on these data, we can conclude that although aldosterone antagonists are non-antiarrhythmic drugs, they have a significant preventive effect on SCD. The available data have focused particularly on the patients with low ejection fraction and congestive heart failure. New studies are needed to expand the indications to use aldosterone antagonists to prevent SCD. Potential mechanisms by which these drugs prevent SCD include prevention of aldosterone-induced cardiac and arterial fibrosis, improvement in arterial compliance, reduction of the adverse effects of aldosterone on cardiac remodelling, improvement of endothelial function and NO activity, improvement in the autonomic nervous system function via a reduction in sympathetic nervous system tonus, improvement in HRV and baroreflex sensitivity, and an increase in myocardial norepinephrine uptake By decreasing urinary excretion of potassium and magnesium, aldosterone antagonists also aid in protecting against life-threatening ventricular arryhthmias.

Upon completion of the chapter, the student will be able to:

Patients with right ventricular pacing and heart failure may be candidates for resynchronisation therapy with the upgrading to biventricular pacing.

The procedure has been shown to be simple and safe. In addition, the results of the above-mentioned studies are encouraging and show that upgraded patients may profit from a better quality of life. However, the life expectancy of these patients remains to be investigated.