Development of Transcatheter Aortic Valve Implantation and its Clinical Implications

In the early 1990s the concept of transcatheter aortic valve implantation (TAVI) appeared challenging and totally unrealistic. It was a true “resurrection” for Cribier and his whole team performing the first TAVI in an inoperable patient in 2002, using a transeptal antegrade approach and balloon-expandable aortic valve prosthesis. Since then TAVI has been performed in more than 50000 patients worldwide. TAVI is currently indicated in patients with severe symptomatic aortic stenosis (AS) and acceptable life expectancy who are not suitable for aortic valve replacement (AVR) (indication class IB) or as an alternative to aortic valve replacement (AVR) in selected high-risk operable patients (class IIB), according to the “Heart Team” assessment.  The TAVI Heart Team comprised of clinical cardiologists, interventionalists, surgeons, anaesthetists and imaging specialists with expertise in the treatment of valve disease, selects patients suitable for TAVI taking into account advantages and disadvantages of both AVR and TAVI. A logistic EuroSCORE ≥20% (logistic EuroSCORE I tends to overestimate observed mortality risk by a factor of 2 to 3 and a newly updated logistic EuroSCORE II is currently available in clinical practice) or a Society of Thoracic Surgeons (STS) score >10% are suggested as indications for TAVI therapy. Recent publications have identified a number of baseline variables independently associated with mortality or poor outcome in patients undergoing TAVI (low body mass, functional status, left ventricular dysfunction, NT-proBNP, prior stroke, diabetes, chronic kidney disease, anemia, severe tricuspid and mitral regurgitation, porcelain aorta or history of chest radiation) which could be integrated into new scoring systems to quantify and predict the prognosis of TAVI both in the immediate and in the long term... (excerpt

Device Therapy in Refractory Heart Failure

Advanced heart failure (HF) has been defined as persistent symptoms that limit daily life despite optical medical therapy, corresponding to New York Heart Association (NYHA) class III/IV symptoms or to the newer classification of stage D HF (ACC/AHA staging classification). It affects 10% of the HF population and is associated with a poor quality of life, recurrent hospitalizations and a mortality approaching 50% at 1 year and 80% at 5 years. Despite the widespread use of angiotensin converting enzyme (ACE) inhibitors, beta adrenergic blocking agents and spironolactone which improve the prognosis in mild to moderate stages, HF remains a progressive disease leading to decompensation and demand of both inotropic agents (class III recommendation according to ACC/AHA guidelines, considered solely for palliation in patients with end-stage disease) and diuretics to treat hypotension, impaired renal function and pulmonary congestion.Heart transplantation (HT) is associated with nearly 90% 1-year survival, 60% 10-year survival and 95% freedom from symptoms and activity limitations in survivors throughout the follow-up period. Nevertheless, the lack of available donors and the large number of patients, who do not meet the criteria for transplantation, have spurred interest in cardiac resynchronization therapy (CRT) and mechanical circulatory support (MCS), providing alternatives for patients waiting for HT (bridge to transplantation, BTT), patients who are ineligible for HT (destination therapy, DT) or patients who are anticipated to recover after left ventricular unloading (bridge to recovery, BTR)... (excerpt

What is New in the ESC Guidelines for the Management of Atrial Fibrillation

The European Society of Cardiology (ESC) and the European Heart Rhythm Association (EHRA) have developed the 2010 Clinical Practice Guidelines covering atrial fibrillation (AF), the most common cardiac arrhythmia occurring in 1-2% of the general population. Advance has been made regarding the dynamic development of AF from a preclinical state to an irreversible cardiac arrhythmia and a novel classification of AF has been adopted based on the presentation and duration of the arrhythmia: first diagnosed, paroxysmal, persistent, long-standing persistent and permanent AF are the 5 types of AF in use for clinical management of patients with AF.Structural and electrical remodelling are hallmarks of the pathophysiological changes facilitating the initiation and perpetuation of AF. While atrial fibrosis was the main cause of nonhomogeneity of conduction according to earlier ESC guidelines, nowadays any kind of structural abnormality (inflammatory changes, amyloid deposit, apoptosis, necrosis, hypertrophy, microvascular changes, etc.) is believed to trigger the electrical dissociation between muscle bundles and permit small re-entrant circuits to stabilize the arrhythmia. The adage ‘atrial fibrillation begets atrial fibrillation’ describes electrical remodelling due to shortening of atrial refractory period, which is attributed to down-regulation of the L-type Ca2+ inward current and up-regulation of inward rectifier K+ currents. Although the exact role of the genome in the pathogenesis of AF is not known, numerous inherited cardiac syndromes and mutations have lately been associated with AF and should be elucidated. Mutations in the gene coding for atrial natriuretic peptide, loss of function mutations in the cardiac sodium channel gene SCN5A or gain of function mutations in the cardiac potassium channel are related to familial AF and genetic loci close to the PITX2 and ZFHX3 genes are currently associated with enhanced risk for cardioembolic stroke... (excerpt

Lethal Proarrhythmic Effect of Propafenone

A 67-year-old man with history of paroxysmal atrial fibrillation and known ischemic cardiomyopathy, dyslipidemia, hypertension, and chronic renal failure, was admitted via the emergency room with complaints of palpitations. Past medical history was remarkable for prior myocardial infarction in 2007 followed by percutaneous coronary intervention in the left anterior descending and right coronary arteries. Recent echocardiography showed a left ventricular ejection fraction of 30-35%. During the admission he was found to be in atrial fibrillation with a ventricular rate of 110 bpm (Fig. 1) and was given orally a dose of 450 mg of propafenone... (excerpt

“Broken Heart Syndrome”: What Women Should Know

The Takotsubo syndrome or apical ballooning, also known as “broken heart syndrome” (BHS) among a variety of suggested names, was first described by Sato et al in the Japanese population approximately 20 years ago. Since then, it has been increasingly recognized in other countries and in 2006 it was classified as a type of stress cardiomyopathy among acquired cardiomyopathies. The prevalence of the BHS is estimated to be 1-2% of patients presenting with an acute coronary syndrome but higher rates have been reported lately, due to a wider recognition of the syndrome. One of the hallmarks of the BHS is a strict predilection for postmenopausal women (over 90% in most series), whereas men account for less than 10% of cases. It has also been reported that among BHS patients, 43% had a preceding acute medical condition and 27% had a severe emotional or physical stressor associated with a “fight or flight” hypersympathetic response... (excerpt

Cardiology News /Recent Literature Review Third Quarter 2012

TCT Meeting will take place in Miami, 22-26/10/12 HCS Meeting to be held in Athens, 1-3/11/12 AHA 2012 is scheduled for Los Angeles, 3-7/11/12EuroEcho will take place in Athens, 5-8/12/2012HCS Working Group Seminars: Thessaloniki, 14-16/2/2013 ACC Meeting: San Francisco, 9-11/3/13HRS Meeting: Denver, 8-11/5/13EuroPCR: Paris, 21-24/5/13 EuroPace: Athens, 23-26/6/13ESC Congress: Amsterdam, 31/8-4/9/13Dennmark Cohort Study: In Patients with AF, Interruption of Warfarin Confers Increased Short-Term Risk of Death or Thrombo-Embolic Events In total, 48,989 atrial fibrillation (AF) patients receiving warfarin were included in this retrospective cohort study. Of these, 35,396 patients had at least one episode of warfarin treatment interruption. In all, 8255 deaths or thromboembolic events occurred during treatment interruption showing an initial clustering of events during 0–90 days. The first 90-day interval of treatment interruption was associated with a markedly higher risk of death or thrombo-embolism (incidence rate ratio-IRR 2.5) vs the interval of 271–360 days. The authors concluded that in this patient population with AF, almost 3 out of 4 patients on warfarin treatment had one or more periods of treatment interruption. Interruption of warfarin therapy was associated with a significantly increased short-term risk of thrombo-embolism or death during the first 90 days of interruption (Raunso J et al, Eur Heart J 2012; 33: 1886–1892).Left Ventricular Dyssynchrony May Determine Outcome Following CRT in Patients with RBBB and Help in the Selection of CRT Candidates Echocardiography was performed in 561 cardiac resynchronization therapy (CRT) recipients (89 with RBBB & 472 with LBBB) before and 6 months after CRT. RBBB patients had a higher prevalence of male gender, ischemic heart disease, atrial fibrillation, and lower exercise capacity when compared with LBBB patients, despite smaller left ventricular (LV) volumes. In addition, the extent of both interventricular and LV dyssynchrony was less in RBBB patients. At 6 months, RBBB patients also showed limited LV reverse remodelling. LV dyssynchrony and mitral regurgitation were identified as independent predictors of all-cause mortality or heart failure hospitalization among RBBB patients. The authors concluded that RBBB patients referred for CRT exhibit interventricular and LV dyssynchrony, albeit less than their LBBB counterparts; preimplantation LV dyssynchrony may be an important determinant of death or heart failure hospitalization among CRT recipients with RBBB (Leong DP et al, Eur Heart J 2012; 33: 1934–1941)... (excerpt

Bifocal Right Ventricular Pacing: Alternative to Biventricular Pacing for Cardiac Resynchronization Therapy?

A 59-year-old patient with dilated cardiomyopathy, severe systolic left ventricular dysfunction and drug-refractory advanced heart failure (New York Heart Association-NYHA class III-IV symptoms) and prior history of mitral valve replacement was scheduled for implantation of a biventricular pacing system (cardiac resynchronization therapy-defibrillator or CRT-D device). The coronary sinus was cannulated after some effort and a venous coronary angiogram was performed. Although a posterolateral cardiac venous branch was identified to accommodate the left ventricular pacing lead, placement of the lead in this tributary was accompanied by phrenic nerve stimulation, which could not be remedied by moving to more proximal positions where the lead could not be stabilized. Having no other option except for sending the patient to surgery for epicardial lead placement, albeit most difficult and high-risk procedure due to prior history of cardiac surgery, we attempted bifocal right ventricular pacing by placing the composite pacing-defibrillating lead at a low septal position and the left ventricular lead at a very high right ventricular (RV) outflow tract position. The procedure was otherwise uncomplicated and the patient’s post-procedural course remained uneventful. The patient had a good clinical response to this type of bifocal RV pacing over the subsequent days and months with amelioration of his dyspneic symptoms and improvement of his quality of life. At the three-year follow-up he remains in NYHA class II category

Pregnancy and Cardiovascular Disease

The cardiovascular system undergoes significant changes during pregnancy to adapt to and accommodate the increased metabolic demands of the fetus and the mother. These adaptations produce an important hemodynamic burden on patients with underlying heart disease, and confer an increase in morbidity and mortality. Furthermore, pregnancy may cause specific cardiovascular disorders, which can impose a risk to the pregnant woman and to her fetus. It is estimated that in the western world 0.2-4% of all pregnancies are complicated by cardiovascular diseases (CVD). This risk is in the ascending order as the age of first pregnancy is increasing and as the number of cardiovascular risk factors is rising (e.g. smoking, hypercholesterolemia, diabetes, hypertension, obesity). During pregnancy, the most frequent cardiovascular events relate to hypertension (6–8%). On the other hand, in the western world, the most frequent CVD present during pregnancy is congenital heart disease-CHD (circa 75%), while rheumatic heart disease predominates in the other countries (circa 70%) and CHD is seen in ~15%. In pregnant women with heart disease, maternal death is estimated around 1% but it varies depending on the underlying CVD; neonatal complications occur in 20–28% and neonatal mortality ranges between 1% and 4%. In general, CVDs are the most common cause of maternal death during pregnancy in the Western industrialized world.4 Thus, women of child-bearing age with CVD or cardiovascular risk factors should be counseled and managed early by an interdisciplinary team of gynecologists, cardiologists, and, when necessary, cardiothoracic surgeons... (excerpt

Phantom Stent Thrombosis

Initial visualization of only the left circumflex coronary artery during coronary angiography in a 71-year-old patient with prior stenting of the left anterior descending (LAD) coronary artery would have led to an erroneous conclusion of a thrombosed stent and occluded coronary artery with its consequent management problems, before it was disclosed that the LAD originated from a separate ostium