Myocarditis — the focal or diffusion inflammation of a myocardium caused more often infectious is more rare — noninfectious agents, and can be involved in inflammatory process both cardiomyocytes, and intersticial fabric. Myocarditis can arise at any infectious disease, but now myocarditis is most often observed at viral infections. Some medicines (antibiotics, streptocides, Methyldopum, etc.), serums and vaccines belong to the noninfectious factors causing myocarditis. Myocardites arise also at general diseases, for example, a system lupus erythematosus and other system vasculites.
Myocardites can be as isolated (primary), and display of other disease (secondary). On a current distinguish acute, subacute and chronic myocarditis.
Inflammatory process in a myocardium leads to disturbance of its main functions: sokratitelny, automatism, excitability and conductivity. Various expressiveness of inflammatory, toxic and degenerative and dystrophic changes, dominance of defeat of the main substance of connecting fabric, vessels or cardiomyocytes, depth of defeat define pathomorphologic and clinical features of myocardites.
Most often an outcome of myocardites is recovery, but at a heavy current the outcome in a miokarditichesky cardiosclerosis and a dilatatsionny cardiomyopathy can be observed.
Classification of myocardites
Myocardites are subdivided as follows.
On nosological accessory: • primary (isolated): • secondary (symptomatic) — as manifestation system (or the general) diseases.
On an etiology:
Infectious: • virus: Koksaki's viruses And yes In, ESNO-viruses, flu A and B, a cytomegalovirus, viruses of poliomyelitis, Epstein — Barre, an immunodeficiency of the person; • bacterial, rickettsial, spirochetotic: beta and hemolitic streptococci, Corynobacterium diphtheriae, Mycoplasma pneumoniae, Coxiella burnetii (Q fever), Rickettsia rickettsii (spotty fever of the Rocky Mountains), Borrcllia burgdorferi (Lyme's illness); • protozoan: Tripanosoma cruzj (Chagas's illness), Toxoplasma gondii; • metazoyny (trichinosis, echinococcosis); • fungal (candidiasis, cryptococcosis, aspergillosis).
Noninfectious: • allergic (antibiotics, streptocides, Methyldopum, antitubercular drugs, vaccines and serums); • toxic (cocaine, doxorubicine, antidepressants, at action of surplus of catecholamines — at a pheochromocytoma, etc.).
On a pathogeny: • infectious; • toxic; • allergic (immune); • the mixed character.
On localization: • parenchymatous; • intersticial.
On prevalence: • focal; • diffusion.
On a current: • acute; • subacute; • chronic.
On outcomes: • recovery • miokarditichesky cardiosclerosis (heart failure, disturbances of a heart rhythm); • dilatanionny cardiomyopathy.
Clinical displays of myocardites
Myocarditis is often preceded by an acute respiratory disease — myocarditis develops either in time, or after an infectious disease in terms of several days to 4 weeks.
The main complaints of patients with myocarditis are weakness, fatigue, heartbeat, an asthma at loadings, discomfort or dull aches in heart. At heavy myocarditis an asthma is observed at rest, amplifies in horizontal position, peripheral hypostases develop. Almost all patients with myocarditis have complaints connected with disturbances of a cordial rhythm and conductivity: heartbeat, interruptions in cardiac performance, feeling of "dying down", "stop". From disturbances of a heart rhythm the ekstrasistoliya most often meets; the Bouveret's disease and a ciliary arrhythmia are observed at the heavy course of myocarditis. Sometimes at heavy myocarditis the syncopal states caused by disturbances of atrioventricular conductivity or paroxysms of atrial or ventricular arrhythmias develop. Besides, at patients with myocarditis the symptoms characteristic of inflammatory process are observed: perspiration, weakness, subfebrile temperature.
The clinical picture of myocarditis depends on localization, prevalence and expressiveness of inflammatory process in a myocardium.
At focal myocarditis clinical manifestations can be absent — only changes of final part of a ventricular complex on the electrocardiogram and laboratory indicators of activity of inflammatory process are observed. However at localization even of the small center of an inflammation in the field of the carrying-out system serious violations of a heart rhythm and conductivity can take place. At some patients myocarditis is shown only by disturbances of a heart rhythm. Quite often viral myocarditis in connection with a malosimptomnost is not distinguished. Most often outcome of such forms of myocarditis favorable. At the same time there is an opinion that viral myocardites even at a favorable current can be further the cause of development of a dilatatsionny cardiomyopathy.
Diffusion myocarditis, as a rule, proceeds hard. Clinical manifestations are expressed as congestive heart failure, even cardiogenic shock, heavy disturbances of a heart rhythm and conductivity can be observed. On this background often there are thromboembolisms in vessels of a big and small circle of blood circulation. This myocarditis quite often has a fatal outcome or gives an outcome in a dilatatsionny cardiomyopathy.
At 20 — 25% of patients with myocarditis pains of stenokardichesky character are observed. In certain cases anginous character of pains in a thorax, changes of an ECG and increase of cardiospecific enzymes in blood cause the assumption of a myocardial infarction. However clinical supervision does not confirm this diagnosis, and coronary arteries at such patients at coronary angiography are not changed.
Differential diagnosis of myocarditis.
The myocarditis having an easy current should be differentiated with myocardium dystrophy which quite often arises against an infectious disease, or with a vegeto-vascular allotopia. Fast dynamics of clinical manifestations and changes on an ECG in comparison with postinfectious dystrophy of a myocardium is characteristic of acute viral myocarditis with an easy current. Besides, at dystrophy of a myocardium there are no signs of inflammatory process, resistance of displays of a disease to antiinflammatory therapy is observed. At vegeto-vascular dystonia communication of the beginning of a disease with the postponed infection is not characteristic, there are no objective signs of damage of a myocardium, laboratory indicators are not changed, sokratitelny function of a myocardium is kept; besides, there are complaints not only cardial, but also neurotic character, and also numerous complaints from other systems.
Differential diagnosis of chronic or long myocarditis with a dilatatsionny cardiomyopathy is quite difficult. When carrying out the differential diagnosis it is necessary to consider existence of signs of activity of inflammatory process, and also signs of inflammatory defeat of other bodies, perhaps, immune character (an arthralgia or arthritis, a mialgiya, pleurisy, nephrite). In the differential diagnosis of these two diseases the endomyocardial biopsy is important — existence of histologic signs of inflammatory process in a myocardium allows to favor myocarditis.
In the presence at patients with myocarditis of the expressed pain syndrome, a pathological tooth of Q on an ECG, myocardium hypokinesia zones according to EhoKG and increase of activity of myocardial enzymes it is necessary to carry out the differential diagnosis with an acute myocardial infarction. Quite often only dynamic supervision over the patient and coronary angiography allow to exclude an ischemic heart disease.
Treatment of myocarditis
At myocarditis restriction of physical activity, and in hard cases — a high bed rest is appointed to the entire period of activity of inflammatory process and before disappearance of clinical manifestations. The athletes who had myocarditis are recommended to avoid sports loadings before recovery of the sizes of heart, sokratitelny function and disappearance of disturbances of a rhythm; the period of rehabilitation averages 6 months.
Drug treatment of myocarditis includes: • etiological treatment: • pathogenetic treatment; • symptomatic treatment.
At infectious not viral myocardites appoint antibiotics which choice depends on the allocated activator and its sensitivity to antibiotics. Efficiency of purpose of the known antiviral drugs (Remantadinum, an acyclovir, and - interferon, etc.) at acute viral myocarditis is not established now, expediency of their use remains not clear. However it is known that in most cases acute viral myocarditis proceeds favorably and comes to an end with recovery without use of any etiotropic means. At the present stage efficiency of treatment of acute and chronic viral myocarditis by means of the anti-lymphocytic monoclones and means stimulating products of interferon is studied.
Pathogenetic treatment of myocardites includes purpose of anti-inflammatory drugs. At the easy and medium-weight course of myocarditis non-steroidal anti-inflammatory drugs — indometacin, diclofenac, an ibuprofen, etc. are used. However purpose of non-steroidal anti-inflammatory drugs is contraindicated in an acute phase of viral myocarditis (during the first 2 weeks) since they can strengthen damage of cardiomyocytes. Use of glucocorticoids at treatment of myocarditis remains disputable because in experimental conditions their use strengthened necroses of a myocardium and replication of viruses. Besides, it is known that glucocorticoids reduce production of interferon. Purpose of glucocorticoids is considered reasonable at treatment of allergic myocardites, and also at the heavy and recurrent course of myocarditis with a possible autoimmune component of an inflammation when there is no effect at use of usual therapy. The conducted research of an assessment of efficiency of immunosuppressive therapy at myocarditis (The Myocarditis Treatment Trial, 1995) did not find distinctions in the forecast of the patients of control and main group receiving Prednisolonum in combination with Azathioprinum or cyclosporine.
Other directions include treatment of heart failure, disturbances of a heart rhythm and conductivity, tromboembolic episodes. Treatment of heart failure is carried out by the standard means, including cardiac glycosides, diuretics and APF inhibitors. At purpose of cardiac glycosides it is necessary to consider that patients with myocarditis are especially sensitive to these drugs therefore it is necessary to monitor emergence of signs of their possible toxic influence. At purpose of antiarrhytmic drugs it is recommended to avoid whenever possible use of beta adrenoblockers in connection with their negative inotropic effect.