RESULTS
Our literature search yielded 671citations. Of these, 28 full texts were screened and 9 studies were included in the final analysis with an aggregate of 967 patients: 589 in the sarcoid group and 378 in the control group.10,15–22 Females comprised 63.4% and 65.13% of the control and sarcoid groups, respectively. The pooled mean age was 49.2 years in the control group and 50.5 years in the sarcoid group. In the sarcoid group, 62.9% of patients had pulmonary involvement 16.8% had dermatologic involvement. Patients with symptoms or signs of cardiac involvement were generally excluded from individual studies. The study characteristics and baseline characteristics are summarized in Tables 1 and 2 respectively. The pooled mean ejection fraction (EF) was 61.5% and 63.1% in the control and sarcoid groups, respectively. Echocardiographic parameters of the studies are summarized in Table 3. The study by Murtagh et al was included in the analysis of MCEs but was excluded from meta-analysis related to LVGLS and GCS as it had no control group 22. Similarly, the study by Chen et al, was included only in the MCEs analysis as it included patients with cardiovascular symptoms.29 The study flow chart is presented in Figure 1.
Nine studies reported LVGLS in our cohorts.10,15-22The pooled mean LVGLS was significantly lower in the sarcoid group as compared to controls: standard mean difference (SMD) -3.98, 95% confidence interval (CI): -5.32, -2.64, p< 0.001, I2=94.70%, Figure 2.
LVGCS was reported in 4 studies with a total of 266 patients, 164 in the sarcoid group and 102 in the control group. The pooled mean GCS was significantly reduced in the sarcoid group as compared to the controls: SMD: -3.33, 95% CI -4.71, -1.95, p< 0.001, I2= 62.94%, Figure 3 10,16,17,19.
In patients with sarcoidosis , MCEs were reported in 4 studies20,21,23,29 with a total of 335 patients; 58 of those suffered a MCE and 275 did not. Patients who suffered MCEs had significantly lower LVGLS (less negative) than patients who did not. SMD: –3.89, 95% CI -6.14, -1.64, P< 0.001, I2= 83.77%, Figure 4. In patients with sarcoidosis. The pooled hazard ratio (HR) of MCEs with LVGLS as the predictor was, HR= 1.28, 95% CI (1.17-1.40), p< 0.001, I2= 0%%, Supplementary figure 1.20,21,29.
Using the NOS tool to evaluate the risk of bias, out of 9 stars, all studies were awarded 8 to 9 stars and can be described as ‘’moderate to high” in quality. The risk of bias of individual studies is reported in Supplementary appendix..