**4. Clinical manifestations**

The manifestations of sarcoidosis vary and depend on the presence or absence of extracardiac compromise, extension, localization, and activity. The majority of heart signs and symptoms are subsequent to arrhythmia, anomalies in atrioventricular conduction, and ventricular arrhythmia (including sudden death) as well as cardiac failure [4]. A less frequent clinical presentation is vasculitis of the coronary arteries. The clinical presentation ranges from palpitations, dyspnea, chest pain, to cardiorespiratory arrest.

Anomalies in atrioventricular conduction are the most frequent manifestation of cardiovascular compromise. They can have a variable clinical presentation that ranges from fixed prolongation of the PR interval (atrioventricular block degree 1) to the presence of branch blocks and in more advanced cases complete atrioventricular block. A prospective study identified that up to 34% of patients with atrioventricular block who were younger than 60 years old, without an apparently clear cause, were eventually diagnosed with sarcoidosis [9], the reason this entity should always be suspected in young patients who present with these alterations without an evident etiology.

The second form of presentation is ventricular arrhythmias which include the presence of premature ventricular complexes and ventricular tachycardia (sustained and non-sustained), mostly subsequent to an increase in cardiac automatism or a reentrant mechanism around the scar caused by granulomas in the myocardium. This type of compromise takes place in ~30% of patients [5]; even these arrhythmias can be the first manifestation of sarcoidosis [6].

**113**

*Cardiac Sarcoidosis*

**5. Diagnosis**

correlation.

• Cardiac failure

tests must be performed:

• Ventricular arrhythmia

syncope, arrhythmias, or cardiac insufficiency.

extracardiac compromise is found to be due to sarcoidosis.

*DOI: http://dx.doi.org/10.5772/intechopen.85310*

the multivariate analysis [10].

Another form of presentation of arrhythmia is supraventricular tachycardia. In a retrospective study of 100 cases, the global prevalence of these arrhythmias was 32%, with auricular fibrillation being the most frequently detected arrhythmia; the methods used for detection were continuous electrocardiogram, Holter monitoring devices, and electrophysiological studies. The majority of patients were asymptomatic (96%), and after atrial fibrillation, in order of frequency, they had atrial tachycardia and atrial flutter. The presence of diastolic dysfunction, increase in the size of the left atrium, and arterial hypertension were the most important factors in

Sudden death is a more unusual situation in cardiac sarcoidosis, but when it takes place, it is usually subsequent to severe malfunction in atrioventricular conduction or ventricular arrhythmia. It seems that the presence of delayed enhancement with gadolinium in nuclear magnetic resonance imaging correlated with this

In some people, cardiac failure can be the main manifestation, followed by dyspnea, orthopnea, and lower limb edema [11]. The right or left ventricular function may be compromised; there may be disorders of segmental or global contractility, as well as valvular compromise, and pulmonary hypertension [12]. There should be a high degree of suspicion regarding this condition, principally when there is a manifest extrapulmonary clinical picture or antecedents of such condition are not present. The involvement of the epicardial coronary arteries is rare; however, there are reports of cases of vasculitis presenting as acute coronary syndrome and even spontaneous dissection of the coronary arteries, cardiac tamponade, and death in

The diagnosis of this condition in particular starts with a high index of suspicion; other possible causes must not be overlooked, taking into consideration the wide clinical spectrum of this pathology. The treatment of this condition requires a significant medical effort with clinical imaging and, in many cases, histological

Cardiac compromise due to sarcoidosis should be suspected when the following

In addition, clinical suspicion should be higher in all patients with antecedents of extracardiac sarcoidosis that occurred with a cardiovascular symptom such as

Thus, the diagnosis of this pathology starts with clinical suspicion generated after a detailed medical record and an exhaustive physical exam of those conditions that might explain the current clinical picture is ruled out and identification of

The use of complementary studies should follow a logical sequence that supports

or rules out the suspicion generated in the clinic. The following complementary

conditions take place in which the most frequent causes are excluded [15]:

• Advanced atrioventricular block in patients younger than 60 years old

patients without any known antecedents of cardiac sarcoidosis [13, 14].

outcome; however, these findings are yet to be confirmed.

#### *Cardiac Sarcoidosis DOI: http://dx.doi.org/10.5772/intechopen.85310*

*Sarcoidosis and Granulomatosis - Diagnosis and Management*

tious agents such as mycobacteria [8].

**4. Clinical manifestations**

*Stains were negative for mycobacteria and fungi.*

**Figure 1.**

cardiorespiratory arrest.

without an evident etiology.

This is a multisystem condition, of unknown etiology, which affects the lungs in most patients (90%) and usually involves the nodes and mediastinum. Cardiac involvement varies according to the population studied and can reach up to 25% [3]. The typical histological feature is the presence of non-necrotizing granuloma (see **Figure 1**) [6] with a central area rich in macrophages, epithelial cells, giant multinucleated cells, and T CD4-positive lymphocytes. In the periphery, there is an abundant population of T CD8 and CD4 lymphocytes, mast cells, and fibroblasts [7]. The origin of this condition is unknown, but one of the theories proposed is antigenic stimulation due to occupational and environmental exposure and infec-

The manifestations of sarcoidosis vary and depend on the presence or absence of extracardiac compromise, extension, localization, and activity. The majority of heart signs and symptoms are subsequent to arrhythmia, anomalies in atrioventricular conduction, and ventricular arrhythmia (including sudden death) as well as cardiac failure [4]. A less frequent clinical presentation is vasculitis of the coronary arteries. The clinical presentation ranges from palpitations, dyspnea, chest pain, to

*Cardiac tissue biopsy. Fragments of myocardium can be observed with compromise due to multiple epithelial, non-necrotizing, focal, and coalesced granules, which involve about 30% of the tissue analyzed. The granules contain numerous multinucleated giant cells and, in the confluent areas, are associated with interstitial fibrosis.* 

Anomalies in atrioventricular conduction are the most frequent manifestation of cardiovascular compromise. They can have a variable clinical presentation that ranges from fixed prolongation of the PR interval (atrioventricular block degree 1) to the presence of branch blocks and in more advanced cases complete atrioventricular block. A prospective study identified that up to 34% of patients with atrioventricular block who were younger than 60 years old, without an apparently clear cause, were eventually diagnosed with sarcoidosis [9], the reason this entity should always be suspected in young patients who present with these alterations

The second form of presentation is ventricular arrhythmias which include the presence of premature ventricular complexes and ventricular tachycardia (sustained and non-sustained), mostly subsequent to an increase in cardiac automatism or a reentrant mechanism around the scar caused by granulomas in the myocardium. This type of compromise takes place in ~30% of patients [5]; even these

arrhythmias can be the first manifestation of sarcoidosis [6].

**3. Pathogenesis**

**112**

Another form of presentation of arrhythmia is supraventricular tachycardia. In a retrospective study of 100 cases, the global prevalence of these arrhythmias was 32%, with auricular fibrillation being the most frequently detected arrhythmia; the methods used for detection were continuous electrocardiogram, Holter monitoring devices, and electrophysiological studies. The majority of patients were asymptomatic (96%), and after atrial fibrillation, in order of frequency, they had atrial tachycardia and atrial flutter. The presence of diastolic dysfunction, increase in the size of the left atrium, and arterial hypertension were the most important factors in the multivariate analysis [10].

Sudden death is a more unusual situation in cardiac sarcoidosis, but when it takes place, it is usually subsequent to severe malfunction in atrioventricular conduction or ventricular arrhythmia. It seems that the presence of delayed enhancement with gadolinium in nuclear magnetic resonance imaging correlated with this outcome; however, these findings are yet to be confirmed.

In some people, cardiac failure can be the main manifestation, followed by dyspnea, orthopnea, and lower limb edema [11]. The right or left ventricular function may be compromised; there may be disorders of segmental or global contractility, as well as valvular compromise, and pulmonary hypertension [12]. There should be a high degree of suspicion regarding this condition, principally when there is a manifest extrapulmonary clinical picture or antecedents of such condition are not present.

The involvement of the epicardial coronary arteries is rare; however, there are reports of cases of vasculitis presenting as acute coronary syndrome and even spontaneous dissection of the coronary arteries, cardiac tamponade, and death in patients without any known antecedents of cardiac sarcoidosis [13, 14].
