key: cord-301424-nt35k3eg
authors: Ad, Niv; Luc, Jessica G.Y.; Nguyen, Tom C.; Arora, Rakesh C.; Balkhy, Husam H.; Bender, Edward M.; Bethencourt, Daniel M.; Bisleri, Gianluigi; Boyd, Douglas; Chu, Michael W.A.; de la Cruz, Kim I.; DeAnda, Abe; Engelman, Daniel T.; Farkas, Emily A.; Fedoruk, Lynn M.; Fiocco, Michael; Forcillo, Jessica; Fradet, Guy; Fremes, Stephen E.; Gammie, James S.; Geirsson, Arnar; Gerdisch, Marc W.; Girardi, Leonard N.; Kaiser, Clayton A.; Kaneko, Tsuyoshi; Kent, William D.T.; Khabbaz, Kamal R.; Khoynezhad, Ali; Kiaii, Bob; Lee, Richard; Legare, Jean-Francois; Lehr, Eric J.; MacArthur, Roderick G.G.; McCarthy, Patrick M.; Mehall, John R.; Merrill, Walter H.; Moon, Marc R.; Ouzounian, Maral; Peltz, Matthias; Perrault, Louis P.; Preventza, Ourania; Ramchandani, Mahesh; Ramlawi, Basel; Salenger, Rawn; Sekela, Michael E.; Sellke, Frank W.; Stulak, John M.; Sutter, Francis P.; Timek, Tomasz A.; Whitman, Glenn; Williams, Judson B.; Wong, Daniel R.; Yanagawa, Bobby; Ye, Jian; Zeigler, Sanford M.
title: Cardiac Surgery in North America and COVID-19: Regional Variability in Burden and Impact
date: 2020-07-02
journal: J Thorac Cardiovasc Surg
DOI: 10.1016/j.jtcvs.2020.06.077
sha: 
doc_id: 301424
cord_uid: nt35k3eg

Abstract Objective The COVID-19 pandemic has resulted in an increase in hospital resource utilization and the need to defer non-urgent cardiac surgery procedures. The present study aims to report the regional variations of North American adult cardiac surgical case volume and case mix through the first wave of the COVID-19 pandemic. Methods A survey was sent to recruit participating adult cardiac surgery centers in North America. Data in regard to changes in institutional and regional cardiac surgical case volume and mix were analyzed. Results Our study comprises 67 adult cardiac surgery institutions with diverse geographic distribution across North America, representing annualized case volumes of 60,452 in 2019. Non-urgent surgery was stopped during the month of March 2020 in the majority of centers (96%) resulting in a decline to 45% of baseline with significant regional variation. Hospitals with a high burden of hospitalized patients with COVID-19 demonstrated similar trends of decline in total volume as centers in low burden areas. As a proportion of total surgical volume, there was a relative increase of coronary artery bypass grafting surgery (High +7.2% vs. Low +4.2%, p=0.550), extracorporeal membrane oxygenation (High +2.5% vs. Low 0.4%, p=0.328) and heart transplantation (High +2.7% vs. Low 0.4%, p=0.090), and decline in valvular cases (High -7.6% vs. Low -2.6%, p=0.195). Conclusions The present study demonstrates the impact of COVID-19 on North American cardiac surgery institutions as well as help associate region and COVID-19 burden with the impact on cardiac surgery volumes and case mix.

(96%) resulting in a decline to 45% of baseline with significant regional variation. Hospitals with 157 a high burden of hospitalized patients with COVID-19 demonstrated similar trends of decline in 158 total volume as centers in low burden areas. As a proportion of total surgical volume, there was 159 a relative increase of coronary artery bypass grafting surgery (High +7.2% vs. Low +4.2%, 160 p=0.550), extracorporeal membrane oxygenation (High +2.5% vs. Low 0.4%, p=0.328) and 161 heart transplantation (High +2.7% vs. Low 0.4%, p=0.090), and decline in valvular cases (High -162 7.6% vs. Low -2.6%, p=0.195).

Conclusions: The present study demonstrates the impact of COVID-19 on North American 164 cardiac surgery institutions as well as help associate region and COVID-19 burden with the impact on cardiac surgery volumes and case mix.

The coronavirus disease 2019 (COVID-19) pandemic has had an unprecedented impact and redirect limited resources and personnel for the treatment of patients with COVID-19, 9 nonurgent cardiac surgical services have been deferred per national and regional policies as well as 174 recommendations from the American College of Surgeons and Society of Thoracic Surgeons 175 (STS) COVID-19 Taskforce. 1 Patients with cardiovascular disease, in particular, those with 176 pathology warranting surgical intervention, are often unstable at presentation to the hospital, or 177 may become very symptomatic while waiting for their procedure. Therefore, during the 178 pandemic most operated patients required urgent intervention. 10 Furthermore, it is anticipated 179 that a progressive increase in deferred cases during the pandemic that will require completion 180 within a limited timeframe once restrictions ease. 11

The effect of COVID-19 on North American cardiac surgical volumes, resource 182 management, and outcomes remains unclear. Understanding the impact of COVID-19 on 183 cardiac surgical volumes and the potential regional and institutional differences in crisis 184 management may provide guidance on post-pandemic hospital operating capacity required to 185 treat deferred cases. 8, [11] [12] [13] In addition, information on the extent of deferred patients can help 186 institutions to proactively prepare to reduce the risk of increased morbidity and mortality for 187 patients waiting for procedures. 3

The present study aims to report the collective North American adult cardiac surgical 189 experience with COVID-19 through the evaluation of changes in cardiac surgical case volume, 190 case mix and outcomes, as stratified by hospitals with high and low burden of hospitalized 191 patients with COVID-19.

Study Design center to recruit participating centers (Supplementary Table 1 

Categorical data were expressed as counts and percentages, and chi-square test was used to 226 analyze differences between groups. Statistical analyses were performed using Stata (Stata

Corp, College Station, TX) with significance at an alpha level of 0.05. Table 1 237 and 2.

Academic centers comprised the majority (n=53, 79%), with institutions with a high 239 burden of COVID-19 more likely to be academic centers (High burden 91% vs. Low burden 240 48%, p=0.003) and to be larger institutions in terms of hospital beds (High 916 vs. Low 561, 241 p=0.009), intensive care unit beds (High burden 163 vs. Low burden 69, p=0.003) and operating 242 room capacity (High burden 55 vs. Low burden 32, p=0.043) ( Table 3 ). All institutions reported 243 to have curtailed non-urgent cardiac surgical operations with the majority having instituted these 244 policies between March 15-31, 2020 (n=48, 72%), followed by March 1-14, 2020 (n=15, 22%) 245 and the remaining April 1, 2020 onwards (n=4, 6%) ( Table 2) .

The majority of centers have converted medical wards to COVID-19 treating areas 249 (70%), followed by surgical wards (34%), cardiac surgical intensive care units (CSICU) (28%), 250 convention centers or public facilities (21%), operating rooms (15%), ground-up construction 251 with tents or buildings (13%) and cardiovascular care units (7%). Overall, a minority of cardiac 252 surgeons (25%) and trainees (28%) required re-deployment to alternative duties (Table 2) .

COVID-19 treating facilities and re-deployment of surgeons and trainees, with the highest 255 proportion of institutions located in the Northeast region of the USA, which also has the highest 256 burden of COVID-19. When stratified by burden of hospitalized patients with COVID-19, 257 institutions with high burden were more likely to require conversion of alternative locations to 258 COVID-19 treating areas (p=0.020) and re-deployment of surgeons (High burden 59% vs. Low 259 burden 9%, p=0.001) and trainees (High burden 68% vs. Low burden 9%, p=0.001) to 260 alternative duties (Table 3) . (Table 2) .

Recognizing the potential deleterious impact of delayed cardiac surgical operations to 299 conserve hospital resources and personnel for the treatment of patients with COVID-19, the 300 majority of institutions have some mechanism of allowing pre-operative cardiac surgical patients 301 to seek expert opinion without the need to venture into the emergency department (82%). Of 302 those institutions with this mechanism for patients to seek help, the majority of modalities were 303 follow-up as needed by providing patients with a contact number to reach out to if there are any 304 concerns (85%), whereas, some institutions pro-actively reached out to deferred patients every seek care without going to the emergency department, with fewer institutions in the Northeast of 308 the US (60%) and Eastern Canada (78%) having such mechanisms in place. Importantly, these 309 were associated with cardiac surgeon regional differences in the use of telemedicine, with 310 telemedicine utilized in only 27% of institutions in Northeast US and 22% of institutions in 311 Eastern Canada (78%) ( Table 2 ). This is further corroborated by institutions with high COVID-19 312 burden being less likely to utilize telemedicine than those with low COVID-19 burden (High 77% 313 vs. Low 98%, p=0.012) ( Table 3) .

Among all institutions combined, there were a total of 9,820 patients hospitalized with 317 confirmed COVID-19 and 4,820 with suspected COVID-19 identified at the reporting centers. 

With over 4 million cases worldwide at the time of publication, the COVID-19 pandemic 327 presents a public health crisis that challenges the availability of healthcare personnel and 328 resources. 12 The impact of COVID-19 has been felt differently across the cardiovascular 329 community at the national and regional levels due in part to differences in prevalence of 330 infection rates, and the social and healthcare system response. 14 331

In this comprehensive survey report of the effect of COVID-19 on cardiac surgical 332 institutions in North America with diverse geographic distribution, we demonstrate that cardiac 333 surgical case volumes have declined to 45% of baseline following COVID-19 with national and 334 regional variation. Interestingly, the trend of decline in the number of cases was of the same for 335 institutions that were in high COVID-19 burden areas compared to those in low burden areas, 336 indicating a consistent response from institutions in the preparation or confrontation with 337 COVID-19. Institutions with high COVID-19 burden had significant decline in total case volume, 338 with change in case mix, that did not meet statistical significance, largely providing urgent or 339 emergent care for procedures, such as CABG, ECMO and heart transplantations, rather than 340 valvular and aortic surgical cases.

Operative outcomes of patients with COVID-19 undergoing a cardiac surgical procedure 342 remains unknown. Pooling the collective experience of 67 North American centers in this study, 343 we demonstrate that overall, unadjusted mortality rate for patients with confirmed or suspected 344 COVID-19 who underwent cardiac surgical operations was 8%. Furthermore, we report the 345 combined North American experience of outcomes of ECMO in the management of COVID-19 346 was associated with higher survival than some previous reports (n=131, of which 82% still alive 347 either decannulated or still supported). These results compare favorably to those previously 348 reported in a systematic review and meta-analysis of patients with COVID-19 who underwent though we are unable to elucidate any further outcomes beyond survival alone. 

The implications of deferred cardiac surgical operations remain unknown, however, prior 362 studies examining deferral of cardiac surgical operations due to limited capacity has been 363 associated with an increase in operative mortality for patients on the waiting list. [17] [18] [19] The current 364 analysis is important given the poor outcomes with the natural history of cardiac surgical 365 disease, such as severe aortic stenosis with reported mortality rates whilst awaiting surgical 366 treatment to be as high as 3.7% at one month and 11.6% at six months; 19 whereas, for patients 367 awaiting CABG, median waiting list mortality rates can be as high as 2.6%-11.0% per month. 17

Another emerging concern of the cardiovascular community is patient reluctance to seek 369 care at a hospital during the COVID-19 outbreak, which has been inferred from the recent 40% 

There is a need for intensified triage, patient counselling, empowerment and proactive 381 follow-up, 21 with the provision of virtual emergency care triage for cardiovascular patients, 22 to 382 allow for timely evaluation without subjecting patients to unnecessary travel to the emergency 383 department. Ultimately, with reduced access to diagnostic testing and operations, there is a 384 concern of a surge of patients with cardiovascular disease that will require treatment. Institutions 

America during the COVID-19 pandemic and change in cardiac surgery case mix. (72) April 1, 2020 onwards 0 (0) 0 (0) 1 (14) 1 (14) 1 (11) 1 (11) 0 (0) 4 (6) 

Adult cardiac surgery during the COVID-19 Pandemic

Programmatic Responses to the Coronavirus 11

Responding to Covid-19 -A Once-in-a-Century Pandemic?

A National Medical Response to Crisis -The Legacy of World War

Safe Reintroduction of Cardiovascular 476 Services during the COVID-19 Pandemic

Poor survival with extracorporeal membrane oxygenation in acute 480 respiratory distress syndrome (ARDS) due to coronavirus disease 2019 (COVID-19): 481 Pooled analysis of early reports

Extracorporeal Life Support Organization -ECMO and ECLS > Registry > Full

Mortality while waiting for aortic valve

Abbreviations: CABG, coronary artery bypass grafting surgery; COVID-19, coronavirus disease 2019; ECMO, extracorporeal membrane oxygenation; ICU, intensive care unit; MCS, mechanical circulatory support

Abbreviations: CABG, coronary artery bypass grafting surgery

cardiac surgery intensive care unit; ECMO, extracorporeal membrane oxygenation; ICU, intensive care unit

MCS, mechanical circulatory support. ER, emergency room

None.

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