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Heart failure (HF) treatment is based on pharmacological therapy, interventional and surgical procedures and cardiac devices implantation. Implantable devices are primarily used to prevent sudden death as with the implantable cardioverter-defibrillator (ICD), to treat left ventricular dysfunction and complete left bundle branch block through cardiac resynchronisation therapy (CRT), eventually also associated with ICD (CRT-D), and to treat bradyarrhythmias with the cardiac pacemaker (PM).

Patients with the advanced stage of disease admitted to the cardiac intensive care unit (CICU) present different symptoms that affect the quality of life and sometimes survival. Dyspnea, pain, thirst, mood disorders (especially delirium), nausea, and constipation are the main symptoms. These are discussed in detail throughout the chapter.

Prognosis, together with therapy, is one of the physician’s aims when formulating a diagnosis.

Patients with irreversible malignant and non-malignant diseases have comparable mortality rates, symptom burdens, and quality of life issues; however, non-cancer patients seldom receive palliative care (PC) or receive it late in their disease trajectory. To explore the characteristics of non-cancer patients receiving PC in northern Italy, as well as the features and outcomes of their care, we retrospectively analyzed the charts of all non-cancer patients initiating PC regimens during 2019 in three publicly funded PC departments in Italy’s populous Lombardy region. We recorded the baseline variables (including data collected with the NECPAL CCOMS-ICO-derived questionnaire used since 2018 to evaluate all admissions to the region’s PC network), as well as treatment features (setting and duration) and outcomes (including time and setting of death). Of the 2043 patients admitted in 2019, only 12% (243 patients—131 females; mean age 83.5 years) had non-oncological primary diagnoses (mainly dementia [n = 78], heart disease [n = 55], and lung disease [n = 30]). All 243 had Karnofsky performance statuses ≤ 40% (10–20% in 64%); most (82%) were malnourished, 92% had ≥2 comorbidities, and 61% reported 2–3 severe symptoms (pain, dyspnea, and fatigue). Fifteen withdrew or were discharged from the study PCN; the other 228 remained in the PCN and died in hospice (n = 133), at home (n = 9), or after family-requested transfer to an emergency department (n = 1). Most deaths (172/228, 75%) occurred

The pandemic infection caused by the virus SARS-CoV-2 has determined a severe imbalance between demand and actual supply of intensive care. The shortage of intensive care units (ICU) beds and ventilators for the treatment of patients with severe respiratory failure produced angst in the clinicians/intensivists who have to decide which patients admit to ICU and in which patients to implement palliative care. They have to apply specific clinical and ethical criteria, in emergency conditions. Proportionality and appropriateness criteria should be integrated with equity, equality, utility criteria, widening the distributive justice concept from the right of the patient to receive all available therapies to a right resources allocation during shortage, guided by public health ethic. The clinical criteria should include the disease severity, the number and severity of comorbidities, frailty, the organ failures and their stage, the patient's age, the functional autonomy and cognitive status. Consequently the first come-first served rule to ICU admission should not be applied. The patients not admitted to ICU due to clinical reasons and advanced stage diseases should receive a high quality palliative care, to obtain a good symptoms control (mainly dyspnea, anxiety and delirium) and to implement palliative sedation at the end of life. Finally particular attention should be paid to the bereavement management of the family/caregivers and in the right approach of psychological problems and Post-Traumatic Stress Disorder of health workers involved in the pandemia.

The Italian law 219/2017, enacted on January 31, 2018, regulates patients' informed consent, personalized care planning and advance directives. The law provides for patient's self-determination in all phases of life. This also applies to patients suffering from chronic, progressive, terminal disease such as heart failure. In fact, the clinical and psychosocial trajectory for heart failure patients demands an interdisciplinary, systemic approach. Advance directives should be tailor-made to patient's needs and dynamically updated through the course of the disease according to patient's and family informed and shared decision-making. Healthcare professionals will require education and training to stay up to the task both clinically, psychologically and emotionally.

Treatment of patients with heart failure is based on drugs, cardiac surgery and implantable cardiac devices to prevent sudden cardiac death (implantable cardioverter-defibrillator [ICD]), to reverse left ventricular dysfunction associated with left bundle branch block (cardiac resynchronization therapy) or mechanical circulatory support in more advanced phases of heart failure (left ventricular assist devices [LVAD]).During the follow-up, patients may die from progression of their underlying heart disease or from non-arrhythmic causes, such as malignancies, multi-organ failure, stroke, etc., without benefits by implanted devices. Patients implanted with ICD could die from non-arrhythmic causes, without appropriate shocks until the last few days or weeks of their life. These events occur roughly in 30% of patients, mainly in the last 24 h before death. LVAD therapy may induce significant complications, such as infections, hemorrhagic stroke, thromboembolism, right ventricular failure. In these cases, inappropriate and even appropriate shock deliveries by ICD can no longer prolong life and may simply lead to pain and reduced quality of life, as well as LVAD may prolong life with painful distress due to complications. Therefore, it appears important to discuss early with the patients and their relatives about deactivation of ICD or LVAD at the end of life. The goal of this paper is to provide an overview of the ethical, clinical and communication issues of cardiac implanted device deactivation, with a special focus on issues associated with advance care planning, which require shared decision-making, including those related to end of life decisions (advance directives). Palliative care should be early implemented, particularly in patients with LVAD.

Prognosis of advanced heart failure (HF) patients, often elderly, frail and with multiple comorbidities, has significantly improved due to recent advancements in interventional cardiology. A multidisciplinary approach is essential in order to better identify patients that could benefit from invasive procedures, avoiding futility. For patients with HF, the Multidimensional Prognostic Index could help the clinician in predicting not only the prognosis but also future quality of life. For cardiac surgical candidates, predictive scores should combine traditional mortality scores with geriatric parameters including nutritional status, screening of delirium, disabilities and comorbidities, in order to help the Heart Team in taking the right approach (i.e. conservative vs invasive strategies). Similarly, the indication to the implantation of a cardioverter-defibrillator or to ablative procedures should consider both the complication rates and the real impact on the quality of life considering the expected net clinical benefit.In the terminal stages of HF the therapeutic target should be oriented to a palliative care approach. In this perspective, the figure of the palliativist plays a role of growing interest and should be integrated into the HF multidisciplinary team.

Palliative care is indicated in patients with heart failure since the early phases of the disease, as suggested by international guidelines. However, patients are referred to palliative care very late. Many barriers could explain the gap between the guidelines’ indications and clinical practice. The term palliative is perceived as a stigma by doctors, patients, and family members because it is charged with negative meanings, a poor prognosis, and no hope for improvement. Many authors prefer the term supportive care, which could facilitate a discussion between doctors, patients, and caregivers. There is substantial variation and overlap in the meanings assigned to these two terms in the literature. Prognosis, as the main indication to palliative care, delays its implementation. It is necessary to modify this paradigm, moving from prognosis to patients’ needs. The lack of access to palliative care programs is often due to a lack of palliative care specialists and this shortage will be greater in the near future. In this study, a new model is proposed to integrate early over the course of the disease the palliative care (PC) specialist in the heart failure team, allowing to overcome the barriers and to achieve truly simultaneous care in the treatment of heart failure (HF) patients.

Early palliative care (PC) clearly demonstrated its efficacy in patients with heart failure (HF), reducing symptom burden, mainly pain and depression, improving quality of life, and reducing the access to the health care system. However, there are not conclusive data on economic cost reduction. The reasons are related to the few patients involved in the studies dedicated to this topic, to the different clinical settings, different modalities of provision and funding of PC, and different timing of PC implementation. PC was not shown to reduce mortality nor hospital readmissions in randomized trials.The unanswered questions will be clarified only in larger studies, defining specific clinical settings, goals to achieve and standardizing the provision and funding modalities in the different countries.

Purpose of review The number of patients who die in the hospital in the Western world is high, and 20-30% of them are admitted to an ICU in the last month of life, including those in cardiac ICUs (CICUs) where invasive procedures are performed and mortality is high. Palliative consultation is provided in only a few cases. The ethical and decisional aspects associated with the advanced stages of illness are very rarely discussed. Recent findings The epidemiological and clinical landscape of CICUs has changed in the last decade; the incidence of acute coronary syndromes has decreased, whereas noncardiovascular diseases, comorbidities, the patients' age and clinical and therapeutic complexity have increased. The use of advanced and invasive treatments, such as mechanical ventilation, mechanical circulatory support and renal replacement therapies, has increased. This evolution increases the possibility of developing a life-threatening clinical event. Summary This review aimed to analyze the main epidemiological, clinical, ethical and training aspects that can facilitate the introduction of supportive/palliative care programs in the CICU to improve symptom management during the advanced/terminal stages of illness, and address such issues as advance care planning, withdrawing/withholding life-sustaining treatments, deactivation of implantable defibrillators and palliative sedation.

In the last few years, important changes have occurred in the clinical and epidemiological characteristics of patients that were admitted to cardiac intensive care units (CICU). Care has shifted from acute coronary syndrome patients towards elderly patients, with a high prevalence of non-ischemic cardiovascular diseases and a high burden of non-cardiovascular comorbid conditions: both increase the susceptibility of patients to developing life-threatening critical conditions. These conditions are associated with a significant symptom burden and mortality rate and an increased length of stay. In this context, palliative care programs, including withholding/withdrawing life support treatments or the deactivation of implanted cardiac devices, are frequently needed, according to the specific guidelines of scientific societies. However, the implementation of these recommendations in clinical practice is still inconsistent. In this review, we analyze the reasons for this gap and the main cultural changes that are required to improve the care of patients with advanced illness.

Sudden cardiac death (SCD) can affect patients with ischemic or non-ischemic left ventricular dysfunction. Automatic implantable cardioverter-defibrillator (ICD) implantation is the most effective option for the treatment of malignant ventricular tachyarrhythmias; however, the procedure is burdened with known significant risks, even in the long term.In patients at high risk of SCD, either real or perceived, without a definite indication to ICD implantation, wearable cardioverter-defibrillators have been shown to offer effective temporary protection in different clinical settings, for patients with recent high-risk myocardial infarction with left ventricular dysfunction, even after myocardial revascularization procedures, heart failure with reduced ejection fraction, newly diagnosed dilated cardiomyopathy, ICD post-explant phase for infection, and bridge to cardiac transplantation.The purpose of this review is to describe the technical aspects and clinical results available in the literature on the use of wearable cardioverter-defibrillators, with particular reference to safety, efficacy, costs and patient selection, together with current and unconventional indications.The authors also report the first data related to their personal experience.

Heart failure (HF) is one of the leading causes of hospitalization in high-income countries and has a profound negative impact on quality of life. In the United States there are more than 900,000 new cases per year and over one million hospital admissions with a primary diagnosis of HF. A prevalence of 6,500,000 cases (2.2% of the population of aged20 years) was estimated for the US in 2014, in which there were 300,000 related deaths. Although survival has increased, thanks to the pharmacological and non pharmacological therapy, roughly 50% of HF patients die within 5 years of being diagnosed. HF is a chronic, progressive and incurable syndrome characterized by alternating periods of apparent stability and acute exacerbations, with frequent hospitalizations. Patients with HF experience a high level of symptoms and symptom burden over time, particularly at the end of life. In addition to classic symptoms such as dyspnea and edema, patients with HF frequently suffer additional symptoms such as pain, depression, gastrointestinal distress, thirst, fatigue and psychological distress. In HF patients the symptom burden is similar to cancer patients, but patients with advanced HF, in comparison to advanced cancer patients, have a greater number of physical symptoms, worse depression status and lower spiritual well-being. There is evidence that HF patients have the same palliative needs as cancer patients, roughly in 40% of cases, but only 20% actually are admitted to hospice programs in US. This situation seems to be the consequence of cultural gap between guidelines, addressing palliative care and HF, and clinical practice. Bridging this gap is a priority to implement an holistic approach to advanced HF.

Admissions to the intensive care unit at the end of life of patients with chronic non-malignant diseases are increasing. This involves the need for the development of palliative care culture and competence, also in the field of intensive cardiology. Palliative care should be implemented in the treatment of all patients with critical stages of disease, irrespective of prognosis, in order to improve the quality of care at the end of life.This review analyzes in detail the main clinical, ethical and communicational issues to move toward the introduction of basics of palliative care in cardiac intensive care units. It outlines the importance of shared decision-making with the patient and his family, with special attention to withholding/withdrawing of life-sustaining treatments, palliative sedation, main symptom control, patient and family psychological support.

The number of cardioverter-defibrillator implants is increasing worldwide, with the main indication being primary prevention of sudden cardiac death. During the follow-up, patients may die from progression of their underlying heart disease or from nonarrhythmic causes, such as malignancies, dementia and lung disease, without receiving appropriate shocks until the last few days or weeks of their life. These events occur roughly in 30% of patients, mainly in the last 24 hours before death. In this case, inappropriate and even appropriate shock deliveries can no longer prolong life and may simply lead to pain and reduced quality of life. Therefore, it appears important to discuss early with the patients and their relatives about deactivation of the implantable cardioverter-defibrillator (ICD) at the end of life.The goal of this review is to provide an overview of the ethical, clinical and communication issues of ICD deactivation, with a special focus on patients' wishes. It is outlined that patients are not adequately informed about risks and benefits of ICD and the option of ICD deactivation; the doctors are not used to discuss with the patients the topics of end-of-life decisions. Complete information must be part of current informed consent before ICD implantation and should be updated during the follow-up, with special attention to patients with heart failure in relation to their prognosis and advance directives, as suggested by international guidelines.

Medical futility refers to interventions that are unlikely to produce any significant benefit for the patient. Medical and technological resources allow many patients affected by advanced cardiovascular diseases to receive more aggressive and expensive treatments than ever before. This wide range of available options can frequently lead to the delay of complex end-of-life decisions, such as starting palliative care programs. Medical futility is a daily problem, with significant ethical implications and concerns about the respect of the main ethics points: non maleficence, patient's autonomy, and justice. This paper examines some considerations and applications of the concept of medical futility, particularly about the various definitions of futility, the complexities of management when care is considered futile and the ethical and clinical criteria to withdrawing or withholding aggressive treatments. The patient-centered care, based on physician-patient communication, seems to be the best approach to this problem, even with a patient with advanced heart disease. Finally, the increasing power of technology and its relationship with the current cultural values of the developed societies are outlined, particularly when end-of-life decisions are addressed.

The electrocardiogram (ECG) is a specific but relatively insensitive tool for diagnosing acute cor pulmonale, which is almost always caused by pulmonary embolism. Acute overload of the right ventricle is manifested by a typical triad of ECG features referred to as the S1Q3T3 complex or McGinn and White triad. It includes the presence of S waves in lead I and Q waves with T-wave inversion in lead III (Fig. 14.1). Acute cor pulmonale can also be associated with right axis deviation, transient right bundle-branch block (RBBB), and T-wave inversion in the right precordial leads (Fig. 14.2). It has been suggested that inverted T waves in lead V2 or V3 are a common ECG sign of massive pulmonary embolism. In another study on pulmonary embolism, the pseudoinfarction pattern (QR in V1) and T-wave inversion in lead V2 were strongly correlated with the presence of right ventricular dysfunction and independent predictors of an unfavorable clinical outcome.

The heart has the capacity to contract regularly following the delivery of an appropriate electrical stimulus (i.e., adequate in both amplitude and duration) at any point on its surface. In clinical settings, this stimulation is achieved with pacemakers (PM). These devices consist of a pulse generator and one or more leads, which are inserted into the right chamber of the heart (and sometimes the coronary sinus as well) and used to transmit the electrical impulses to the myocardium (Fig. 10.1). The generator is composed of an energy source (lithium battery) and a series of electronic circuits that characterize the PM activity. The leads are attached by screws to a connector block that links them to the generator. Together, they form a “closed” electrical circuit, the dimensions of which vary depending on whether the leads are unipolar or bipolar. In the former case, the circuit consists of an anode (the PM generator) and a cathode (located at the tip of the lead), and it is quite large. For this reason, it is susceptible to interference by external impulses. Bipolar electrodes have two poles at their tips: a proximal one that serves as the anode and a distal one that functions as the cathode. Circuits composed of bipolar electrodes are smaller and much less vulnerable to external interference.

Reductions in blood flow (and consequently the oxygen supply) to the myocardium can cause transient or permanent damage (ischemia and necrosis, respectively). Atherosclerosis of the coronary arteries is the most common cause. In most cases, the ischemia initially involves the subendocardial layers of the myocardium, which are characterized by a higher metabolic rate and oxygen consumption than the subepicardial layers since they more exposed to extravascular compressive forces (systolic tension, ventricular filling pressure). Only later does the damage extends to the full thickness of the myocardium (Fig. 11.1).

The electrical activity of the heart is governed by the sinoatrial (SA) node (also known as the node of Keith and Flack) (Fig. 1.1), a microscopic structure located in the right atrium, at the junction between the atrium and the superior vena cava. It is made of pacemaker cells, which are intrinsically capable of generating rhythmic electrical impulses at rates that normally range from 60 to 100 beats per minute (bpm). The electrical current that originates here is propagated to the atria along preformed pathways known as the internodal tracts: the anterior internodal tract (known as Bachmann’s bundle), which includes a branch for the left atrium; the middle internodal tract (Wenckebach’s bundle); and the posterior internodal tract (Thorel’s bundle).

Acute pericarditis is associated with inflammation of the subepicardial layers of the myocardium, which are in contact with the pericardium. The electrocardiogram (ECG) can be useful in the diagnosis of this disorder, revealing diffuse ST-segment and T-wave changes that evolve in a characteristic manner and are phase-specific.

As noted in Chap. 1, propagation of the electrical stimulus in the heart can be represented as dipoles. For simplicity’s sake, each dipole is represented as a vector with a negatively charged tail and a positively charged head (Fig. 2.1). ECG electrodes are attached to the surfaces of specific body areas and connected to one another to form leads. The electrical potentials in the heart are recorded by the leads and transmitted them to the electrocardiograph, which is a galvanometric recording device (Fig. 2.2). Vectors travelling away from the recording point are represented by negative deflections; those moving toward the recording point appear as positive waves (Fig. 2.3).

Arrhythmias are cardiac rhythm abnormalities, that is, rhythms differing from the normal sinus rhythm, which is characterized by heart rates ranging from 60 to 100 beats per minute (bpm). When the rate falls below 60 bpm, the patient is said to have a bradyarrhythmia, whereas rates above 100 bpm are referred to as tachyarrhythmias. Electrocardiographic analysis of an arrhythmia is not limited, however, to heart rate (increased versus decreased): it also includes the rhythm (which can be regular or irregular), the origin (supraventricular versus ventricular), and the morphology of the QRS complex (narrow versus wide) (Table 4.1).

The electrocardiograph is a galvanometer calibrated to produce a deflection with an amplitude of 1 cm for every millivolt (mV) of voltage. The electrocardiogram (ECG) is recorded on graph paper divided into small 1-mm squares. At the standard paper speed of 25 mm/s, each small square corresponds to 40 ms (Fig. 3.1). Before the ECG is recorded, the machine must be calibrated to ensure that it is functioning correctly, and the square (or rectangular) calibration mark must be recorded on the tracing.

This group of arrhythmias includes several specific syndromes, the most important of which are

A number of cardioactive drugs can cause changes in the electrocardiogram (ECG), the antiarrhythmic agents in particular. The most important effects produced by these drugs are bradyarrhythmias, which have been discussed in detail in Chap. 5. In this chapter, we will examine some of the specific effects of individual drugs, with special emphasis on their proarrhythmic effects.

In its most common form, the Wolff-Parkinson-White (WPW) syndrome is caused by the presence of an embryonic remnant consisting of an accessory atrioventricular pathway. When the pathway bypasses the AV node and connects the atria directly to the ventricles, it is referred to as the bundle of Kent. Less frequently, the anomalous connection is between the AV node or bundle of His and the ventricles, and it is referred to as the bundle of Mahaim. The bundle of Kent is by far the more common variant. In this case, the excitation wavefront travels simultaneously through the usual pathway (the AV node, which normally slows conduction) and much more rapidly through the accessory pathway, thereby activating the ventricles earlier than usual. As a result, the P-R interval is shortened, and the initial part of the ventricular complex is slurred or notched. This distortion is referred to as a delta wave, and it is pathognomonic for the WPW syndrome. The QRS complex in this case is actually a fusion of the complexes resulting from the two pathways of ventricular activation (Figs. 7.1 and 7.2).

In Italy the birth rate decrease together with the continuous improvement of living conditions on one hand, and the health care progress on the other hand, led in recent years to an increasing number of patients with chronic mono- or multi-organ failures and in an extension of their life expectancy. However, the natural history of chronic failures has not changed and the inescapable disease's worsening at the end makes more rare remissions, increasing hospital admissions rate and length of stay. Thus, when the "end-stage" get close clinicians have to engage the patient and his relatives in an advance care planning aimed to share a decision making process regarding all future treatments and related ethical choices such as patient's best interests, rights, values, and priorities. A right approach to the chronic organ failures end-stage patients consists therefore of a careful balance between the new powers of intervention provided by the biotechnology and pharmacology (intensive care), both with the quality of remaining life supplied by physicians to these patients (proportionality and beneficence) and the effective resources rationing and allocation (distributive justice). However, uncertainty still marks the criteria used by doctors to assess prognosis of these patients in order to make decisions concerning intensive or palliative care. The integrated care pathway suggested in this position paper shared by nine Italian medical societies, has to be intended as a guide focused to identify end-stage patients and choosing for them the best care option between intensive treatments and palliative care.

The therapeutic options related to chronic organ failure are interconnected to the variability of human biological responses and the personal history and choices of the chronically ill patient on one hand, and with the variable human answers to therapies on the other hand. All these aspects may explain the small number and low quality of studies aimed to define the clinical criteria useful in identifying end-stage chronically ill patients, as highlighted through the 2012-2013 Medline survey performed by the task force. These results prevented the grading of scientific evidence. However, taking into account the evidence based medicine definition, the task force believes the clinical reasoning and the individual experience of clinicians as well as the patients and families preferences cannot be replaced "tout court" with a strict methodological research. Accordingly, the working method selected by the task force members was to draw up a set of clinical parameters based on the available scientific literature, submitting it to a peer review process carried out by an expert panel. This paper discusses a set of clinical parameters included in the clinical decision-making algorithm and shared by nine medical societies. For each chronic organ failure these clinical parameters should be intended not as a rigid cutoff system to make a choice between two selected care options (intensive vs palliative), rather as the starting point for a joint and careful consideration regarding the opportunity to adopt the clinical decision-making algorithm care proposed in Part I.

In the last years dramatic changes in clinical and epidemiological characteristics of patients admitted to cardiac intensive care units have been observed. Aging population, non-ischemic cardiovascular diseases, acute and chronic severe comorbidities, all increased the susceptibility to develop life-threatening critical settings. In this context, palliative care programs are needed more frequently. In this review, the ethical and clinical criteria to withdrawing and withholding artificial cardiocirculatory, respiratory and renal supports are analyzed, as well as the cultural delays of cardiologists involved in this peculiar clinical setting.

L’elettrocardiogramma (ECG) nella diagnostica del cuore polmonare acuto, quasi sempre legato ad embolia polmonare, ha una bassa sensibilita, ma buona specificita.

L’elettrocardiografo e un galvanometro tarato in modo che una deflessione di 1 cm di ampiezza corrisponda a 1 m V di voltaggio. La registrazione dell’elettrocardiogramma (ECG) e effettuata su carta millimetrata, fornita di quadratini di 1 mm i lato, con velocita standard di scorrimento di 25 mm/s: a tale velocita ogni quadratino corrisponde a 40 ms (Fig. 3.1). La registrazione dell’ECG va pertanto preceduta dalla taratura dello strumento per verificarne il funzionamento e l’onda quadra cosi ottenuta va registrata su tracciato. Open image in new window Fig. 3.1. ECG con le singole componenti e loro rapporti temporali

L’attivita elettrica del cuore e governata dal nodo seno-atriale (NSA, nodo di Keith e Flack) (Fig. 1.1), microscopica struttura localizzata nell’atrio destro, alla base della vena cava superiore, formato da un insieme di cellule aventi proprieta auto-eccitatorie (cellule pacemaker) e dotato quindi di intrinseca capacita ad emettere ritmicamente impulsi elettrici, ad una frequenza variabile, nella norma, fra 60 e 100 battiti per minuto (bpm). La corrente da qui originata si transmette agli atri attraverso alcune vie preformate, i fasci internodali: il fascio internodale anteriore di Bachmann, che fornisce un ramo per ’atrio sinistro, il fascio internodale iosteriore (di Thorel). L’onda di depolarizzazione elettrica viene convogliata successivamente al nodo atrioventricolare (NAV, nodo di Tawara). Questa seconda stazione fondamentale del sistema specifico di conduzione e posta sul piano atrioventricolare, quasi all’incrocio tra quest’ultimo e i due setti, l’interatriale e l’interventricolare. Open image in new window Fig. 1.1 Anatomia del sistema di eccitoconduzione. NSA, nodo seno-atriale: NAV, nodo atrioventricolare. Per i dettagli vedi testo

Numerosi farmaci attivi sul sistema cardiovascolare possono indurre alterazioni elettrocardiografiche, in particolare i farmaci antiaritmici. Fra gli effetti principali che producono vi sono in primo luogo le bradiaritmie, per la cui illustrazione si rimanda al Capitolo 5. Di seguito vengono invece proposti alcuni esempi piu specifici per le singole molecole, con particolare riferimento agli effetti cosiddetti proaritmici.

Come e stato ricordato nel Capitolo 1, la propagazione dello stimolo elettrico nel cuore puo essere rappresentata con dei dipoli e questi, per maggior semplicita, con dei vettori in cui la testa ha carica positiva e la coda carica negativa (Fig. 2.1). Open image in new window Fig. 2.1 In a fibra miocardica parzialmente depolarizzata (area grigia), in b dipolo e in c vettore, che presenta coda negativa e testa positiva

Gli ingrandimenti atriali sono la conseguenza di un sovraccarico degli atri, di pressione, per ostacolo all’efflusso — ad esempio nella stenosi mitralica —, o di volume, per insufficienza delle valvole atrioventricolari o per shunt.

Si tratta di un gruppo di aritmie che comprende alcune sindromi specifiche, le piu importanti delle quali sono: 1. sindrome del QT lungo (LQTS); 2. sindrome del QT corto; 3. sindrome di Brugada.

Il cuore e un organo in grado di contrarsi regolarmente in seguito all’erogazione, su un punto qualsiasi della sua superficie, di uno stimolo elettrico di ampiezza e durata adeguati.