High Degree Atrioventricular Block Complicated Cardiac Sarcoidosis : Case Report

Cardiac Sarcoidosis (CS) is a rare and deceptive disease affecting young adults with catastrophic results including life threatening arrhythmia, congestive heart failure and even sudden death as the initial presentation. CS has been linked to a significant high morbidity & mortality. We present two patients: The first patient with an initial cardiac event that led us to a diagnosis of Pulmonary and Cardiac Sarcoidosis. A second patient, who was diagnosed initially with pulmonary Sarcoidosis, presented with a severe heart conduction abnormality. Both patients were successfully treated with permanent pacemakers. The dual purpose of our study is first to emphasize the importance of follow up on patients with Non-Cardiac Sarcoidosis for cardiac involvement and secondly to increase awareness of CS as part of a differential diagnosis among young adults with unexplained arrhythmia.


Introduction
Sarcoidosis is a rare, multisystem, granulomatous disease of unknown etiology that most often affects the lungs (over 90%), skin, eyes, and lymphoreticular system [1] [2].Non-caseating granulomas are the pathological hallmark of Sarcoidosis [3].The disease manifests itself worldwide, without regard to gender, age and ethnicity [4] [5] [6] [7].Although it usually develops before the age of 50, the incidence rate displays a biphasic pattern with the first peak between the ages of 25 -39 and the second between the ages of 60 -64 [8] [9].Cardiac involvement in Sarcoidosis occurs in 20% -30% of the patients [10].DOI: 10.4236/wjcs.2018.89015158 World Journal of Cardiovascular Surgery Despite its association with high rates of mortality, sole involvement of the heart is estimate at being 2% -5% of the documented cases, and has the lowest incident manifestation.CS manifestations include conduction disorders, arrhythmias, Atrial and Ventricular arrhythmias, congestive heart failure, valvular pathology, pericardial effusions and sudden cardiac death [11] [12].
The most frequently involved region is the left ventricular free wall, followed by the interventricular septum, often with involvement of the conducting system.The most specific characteristic feature of CS in echocardiogram is interventricular thinning [13].
Less than 5% of patients die from Sarcoidosis.While Sarcoidosis is not commonly fatal, cardiac involvement may be responsible for more than two-thirds of deaths.In Japan, cardiac involvement is more common in older women and responsible for as many as 85% of deaths [14].
Cardiac involvement in patients with Sarcoidosis is increasingly recognized as being associated with a poor prognosis [15].
Early screening for cardiac involvement in patients with known Sarcoidosisin other organ systems is crucial, especially because sudden death may be the first manifestation of CS and prompt treatment can reduce its risk [16].
It is recommended to carry out a detailed clinical history to identify cardiac symptoms (including syncope, pre-syncope or palpitations), a 12-lead electrocardiogram (ECG) and an echocardiogram.
Further screening is advised if any of the initial screening investigations yield an abnormality; cardiovascular magnetic resonance (CMR) or fluorodeoxyglucose positron emission tomography (FDG-PET) [17] [18].
Screening for cardiac involvement in specific clinical presentations in patients without known Sarcoidosis, can also identify CS patients early in their disease course.A clinical diagnosis of CS is critically important in the planning of therapeutic strategy.

Patients and Materials
We describe two CS patients with an initial presentation of a heart conduction abnormality.

Case I
A 43-year-old male, without known chronic illnesses brought to Emergency Room after syncope.The patient denied preliminary complains, previously similar events or decrease in functional capacity.Initial ECG showed prolonged non-conducted P waves indicating complete atrioventricular block (Figure 1-Strip ECG shows Prolonged Non-Conducted P waves (black Arrows) indicate complete atrioventricular block).Temporarily pacemaker was placed.A quick preliminary inquiry eliminates an ischemic cause and electrolytes imbalance.On chest X-Ray there was a suspicion of fullness on hila of the lungs.

Case II
Computed tomography of the chest reveled bilateral mediastinal lymph nodes enlargement (Figure 2-CT scan of the chest showing bilateral lymph nodes

Figure 1 .
Figure 1.Strip ECG shows Prolonged Non-Conducted P waves (black Arrows) indicate complete atrioventricular block.

Figure 2 .
Figure 2. CT scan of the chest showing bilateral lymph nodes enlargement (red arrows) in the mediastinum.

A
58-year-old female who was recently diagnosed with pulmonary Sarcoidosis based on chest CT finding indicated bihilar and mediastinal lymph nodes enlargement (Figure 5-CT scan of the chest showing bihilar and mediastinal DOI: 10.4236/wjcs.2018.89015160 World Journal of Cardiovascular Surgery

Figure 3 .
Figure 3. Gallium PET scan showed multiple foci of increased uptake on mediastinum and axillae (black arrows).

Figure 5 .
Figure 5. CT scan of the chest showing bihilar and mediastinal lymph nodes enlargement (red arrows).

Figure 6 .
Figure 6.Leads ECG show multiple non-conducted P waves (black arrows) with ventricular escape rhythm indicate complete atrioventricular block.

Figure 7 .
Figure 7. Chest X-ray image show bihilar lymph nodes enlargement (red arrows) and dual camber pacemaker with leads in right atria & ventricle (red circles).