Impact of COVID-19 Pandemic on Cardiovascular Testing in Asia

Background

The coronavirus disease-2019 (COVID-19) pandemic significantly affected management of cardiovascular disease around the world. The effect of the pandemic on volume of cardiovascular diagnostic procedures is not known.

Objectives

This study sought to evaluate the effects of the early phase of the COVID-19 pandemic on cardiovascular diagnostic procedures and safety practices in Asia.

Methods

The International Atomic Energy Agency conducted a worldwide survey to assess changes in cardiovascular procedure volume and safety practices caused by COVID-19. Testing volumes were reported for March 2020 and April 2020 and were compared to those from March 2019. Data from 180 centers across 33 Asian countries were grouped into 4 subregions for comparison.

Results

Procedure volumes decreased by 47% from March 2019 to March 2020, showing recovery from March 2020 to April 2020 in Eastern Asia, particularly in China. The majority of centers cancelled outpatient activities and increased time per study. Practice changes included implementing physical distancing and restricting visitors. Although COVID testing was not commonly performed, it was conducted in one-third of facilities in Eastern Asia. The most severe reductions in procedure volumes were observed in lower-income countries, where volumes decreased 81% from March 2019 to April 2020.

Conclusions

The COVID-19 pandemic in Asia caused significant reductions in cardiovascular diagnostic procedures, particularly in low-income countries. Further studies on effects of COVID-19 on cardiovascular outcomes and changes in care delivery are warranted.

Impact of early post-stress LV Dis-sinchrony assessed by TC99m GSPECT myocardial perfusion: ischemic patients vs. normal subjects

Purpose

We aimed to determine the value of early post-stress Tc99msestamibi gated SPECT imaging for detecting changes in the two phase analysis synchrony parameters: Histogram bandwidth (HB) and Standard deviation (SD) in ischemic patients compared to normal subjects.

Methods

We prospectively included normal subjects and consecutive patients who had a positive stress test (angina or ST deviation during stress test). Both groups followed the same GSPECT protocol: an early stress image (acquired at maximum 10 minutes after the tracer injection), a delayed stress image (after 45 min of tracer injection) and the rest image. Phase analysis indices HB and SD were compared from early stress/ rest images and delayed stress/rest images in both groups. We compared the change of SD and HB indices (stress minus rest) for early and delayed images. The ischemic group was divided into mild ischemia (SDS≤3), moderate ischemia (SDS>3 and<8), and severe ischemia (SDS≥8)

Results

Twenty nine normal subjects and 57 ischemic patients were included. Thirty per cent of the ischemic group had mild ischemia, 32% moderate ischemia and 37% severe ischemia. SD and HB values decreased in early and delayed-stress images compared to those of rest images in normal subjects (all p<0,05). In the ischemic group early-stress SD increased compared to rest SD (p<0,05) while delayed- stress SD did not change. Early-stress HB did not change in comparison to rest HB while delayed-stress HB decrease compared to rest HB.The figure shows the comparison of SD and HB between early-stress, delayed-stress and rest images in normal subjects and ischemic patients. The Table shows the comparison of the change of SD and HB indices (stress minus rest) for early and delay images.

Conclusion

LVMS indices obtained by phase analysis of Tc99sestamibi GSPECT imaging, HB and SD decrease significantly when derived from early and delayed stress images compared to rest images in normal subjects. A progressive significant increase in SD and HB values in delayed and early stress images was observed in this population what could be an expression of post-ischemic LV dis-synchrony. Larger amounts of ischemia are related to progressive higher changes in SD and HB from early and delayed stress images versus rest images.

Funding Acknowledgement

Type of funding source: None

Effect of poly (l-lactic acid) scaffolds seeded with aligned diaphragmatic myoblasts overexpressing connexin-43 on infarct size and ventricular function in sheep with acute coronary occlusion

Diaphragmatic myoblasts (DM) are stem cells of the diaphragm, a muscle displaying high resistance to stress and exhaustion. We hypothesized that DM modified to overexpress connexin-43 (cx43), seeded on aligned poly (l-lactic acid) (PLLA) sheets would decrease infarct size and improve ventricular function in sheep with acute myocardial infarction (AMI). Sheep with AMI received PLLA sheets without DM (PLLA group), sheets with DM (PLLA-DM group), sheets with DM overexpressing cx43 (PLLA-DMcx43) or no treatment (control group, n = 6 per group). Infarct size (cardiac magnetic resonance) decreased ∼25% in PLLA-DMcx43 [from 8.2 ± 0.6 ml (day 2) to 6.5 ± 0.7 ml (day 45), p < .01, ANOVA-Bonferroni] but not in the other groups. Ejection fraction (EF%) (echocardiography) at 3 days post-AMI fell significantly in all groups. At 45 days, PLLA-DM y PLLA-DMcx43 recovered their EF% to pre-AMI values (PLLA-DM: 61.1 ± 0.5% vs. 58.9 ± 3.3%, p = NS; PLLA-DMcx43: 64.6 ± 2.9% vs. 56.9 ± 2.4%, p = NS), but not in control (56.8 ± 2.0% vs. 43.8 ± 1.1%, p < .01) and PLLA (65.7 ± 2.1% vs. 56.6 ± 4.8%, p < .01). Capillary density was higher (p < .05) in PLLA-DMcx43 group than in the remaining groups. In conclusion, PLLA-DMcx43 reduces infarct size in sheep with AMI. PLLA-DMcx43 and PLLA-DM improve ventricular function similarly. Given its safety and feasibility, this novel approach may prove beneficial in the clinic.