Effect of COVID-19 Pandemic Lockdown on Emergency Medical Service Utilisation, and Percutaneous Coronary Intervention Volume-An Australian Perspective.

BACKGROUND: Acute coronary syndrome (ACS) admissions and percutaneous coronary intervention (PCI) volume declined during periods of COVID-19 lockdown internationally in 2020. The effect of lockdown on emergency medical service (EMS) utilisation, and PCI volume during the initial phase of the pandemic in Australia has not been well described. METHOD: We analysed data from the Victorian Cardiac Outcomes Registry (VCOR), a state-wide PCI registry, linked with the Ambulance Victoria EMS registry. PCI volume, 30-day major adverse cardiovascular and cerebrovascular events (MACCE; composite of mortality, myocardial infarction, stent thrombosis, unplanned revascularisation, and stroke), and EMS utilisation were compared over four time periods: lockdown (26 Mar 2020-12 May 2020); pre-lockdown (26 Feb 2020-25 Mar 2020); post-lockdown (13 May 2020-10 Jul 2020); and the year prior (26 Mar 2019-12 May 2019). Interrupted time series analysis was performed to assess PCI trends within and between consecutive periods. RESULTS: The EMS utilisation for ACS during lockdown was higher compared with other periods: lockdown 39.4% vs pre-lockdown 29.7%; vs post-lockdown 33.6%; vs year prior 27.1%; all p<0.01. Median daily PCI cases were similar: 31 (IQR 10, 38) during lockdown; 39 (15, 49) pre-lockdown; 39.5 (11, 44) post-lockdown; and, 42 (10, 49) the year prior; all p>0.05. Median door-to-procedure time for ACS indication during lockdown was shorter at 3 hours (1.2, 20.6) vs pre-lockdown 3.9 (1.7, 21); vs post-lockdown 3.5 (1.5, 21.26); and, the year prior 3.5 (1.5, 23.7); all p<0.05. Lockdown period was associated with lower odds for 30-day MACCE compared to pre-lockdown (odds ratio [OR] 0.55 [0.33-0.93]; p=0.026); post-lockdown (OR 0.66; [0.40-1.06]; p=0.087); and the year prior (OR 0.55 [0.33-0.93]; p=0.026). CONCLUSIONS: Contrary to international trends, EMS utilisation for ACS increased during lockdown but PCI volumes remained similar throughout the initial stages of the pandemic in Victoria, with no observed adverse effect on 30-day MACCE during lockdown. These data suggest that the public health response in Victoria was not associated with poorer quality cardiovascular care in patients receiving PCI.

Percutaneous coronary intervention outcomes based on American College of Cardiology/American Heart Association coronary lesion classification over 14 years - Melbourne interventional group (MIG) registry.

BACKGROUND: The American College of Cardiology / American Heart Association (ACC/AHA) introduced a coronary lesion classification in 1988 to stratify coronary lesions for probability of procedural success and complications after coronary angioplasty. Our aim is to assess the validity of the ACC/AHA lesion classification in predicting outcomes of percutaneous coronary intervention (PCI) in a contemporary cohort of patients. METHODS: Consecutive PCI procedures performed between 2005 and 2018, were divided into three periods. At each period, the ACC/AHA lesion classification (A, B1, B2, C) was analysed with respect to procedural characteristics, in-hospital and 30-day outcomes, as well as long-term mortality by linkage to the National Death Index (NDI). RESULTS: In total, 21,437 lesions were included with 7399 lesions (2005-2009), 6917 lesions (2010-2014) and 7121 lesions (2015-2018). There was a progressive increase in the number of complex lesions treated over time with ACC/AHA type C (15 %, 21 % and 26 %, p < 0.01). The rate of PCI procedural success decreased with increase in the complexity of lesions treated across all three periods (p < 0.01). Further, in-hospital and 30-day major adverse cardiovascular events (MACE), major adverse cardiac and cerebrovascular events (MACCE) increased across all three time periods (all p < 0.05). CONCLUSIONS: Our study validates the ACC/AHA lesion classification as a meaningful tool for prediction of PCI outcomes. Despite advances in PCI techniques and technology, complex lesion PCI defined by this classification continues to be associated with adverse outcomes.

Prevalence and outcomes of patients with SMuRF-less acute coronary syndrome undergoing percutaneous coronary intervention.

BACKGROUND: There is increasing awareness that patients without standard modifiable risk factors (SMuRFs; diabetes, hypercholesterolaemia, hypertension and smoking) may represent a unique subset of patients with acute coronary syndrome (ACS). We aimed to investigate the prevalence and outcomes of patients with SMuRF-less ACS undergoing percutaneous coronary intervention (PCI) compared with those with SMuRFs. METHODS: We analysed data from the Melbourne Interventional Group PCI Registry. Patients with coronary artery disease were excluded. The primary outcome was 30-day mortality. Secondary outcomes included in-hospital and 30-day events. Long-term mortality was investigated using Cox-proportional hazards regression. RESULTS: From 1 January 2005 to 31 December 2020, 2727/18 988 (14.4%) patients were SMuRF less, with the proportion increasing over time. Mean age was similar for patients with and without SMuRFs (63 years), and fewer females were SMuRF-less (19.8% vs 25.4%, p<0.001). SMuRF-less patients were more likely to present with cardiac arrest (6.6% vs 3.9%, p<0.001) and ST-elevation myocardial infarction (59.1% vs 50.8%, p<0.001) and were more likely to experience postprocedural cardiogenic shock (4.5% vs 3.6%, p=0.019) and arrhythmia (11.2% vs 9.9%, p=0.029). At 30 days, mortality, myocardial infarction, revascularisation and major adverse cardiac and cerebrovascular events did not differ between the groups. During median follow-up of 7 years, SMuRF-less patients had an adjusted 13% decreased rate of mortality (HR 0.87 (95% CI 0.78 to 0.97)). CONCLUSIONS: The proportion of SMuRF-less patients increased over time. Presentation was more often a devastating cardiac event compared with those with SMuRFs. No difference in 30-day outcomes was observed and SMuRF-less patients had lower hazard for long-term mortality.

Prevalence and Predictors of Emergency Medical Service Use in Patients Undergoing Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction.

AIM: We aim to describe prevalence of Emergency Medical Service (EMS) use, investigate factors predictive of EMS use, and determine if EMS use predicts treatment delay and mortality in our ST-elevation myocardial infarction (STEMI) cohort. METHOD: We prospectively collected data on 5,602 patients presenting with STEMI for primary percutaneous coronary intervention (PCI) transported to PCI-capable hospitals in Victoria, Australia, from 2013-2018 who were entered into the Victorian Cardiac Outcomes Registry (VCOR). We linked this dataset to the Ambulance Victoria and National Death Index (NDI) datasets. We excluded late presentation, thrombolysed, and in-hospital STEMI, as well as patients presenting with cardiogenic shock and out-of-hospital cardiac arrest. RESULTS: In total, 74% of patients undergoing primary PCI for STEMI used EMS. Older age, female gender, higher socioeconomic status, and a history of prior ischaemic heart disease were independent predictors of using EMS. EMS use was associated with shorter adjusted door-to-balloon (53 vs 72 minutes, p<0.001) and symptom-to-balloon (183 vs 212 minutes, p<0.001) times. Mode of transport was not predictive of 30-day or 12-month mortality. CONCLUSIONS: EMS use in Victoria is relatively high compared with internationally reported data. EMS use reduces treatment delay. Predictors of EMS use in our cohort are consistent with those prevalent in prior literature. Understanding the patients who are less likely to use EMS might inform more targeted education campaigns in the future.

Clinical Outcomes of Renal Transplant Recipients Undergoing Percutaneous Coronary Intervention.

BACKGROUND: Clinical outcomes of patients with renal transplant (RT) undergoing percutaneous coronary intervention (PCI) remain poorly elucidated. METHOD: Between 2014 and 2021, data were analysed for the following three groups of patients undergoing PCI enrolled in a multicentre Australian registry: (1) RT recipients (n=226), (2) patients on dialysis (n=992), and (3) chronic kidney disease (CKD) patients (estimated glomerular filtration rate [eGFR], 30‒60 mL/min per 1.73 m2) without previous RT (n=15,534). Primary outcome was 30-day major adverse cardiac and cerebrovascular events (MACCEs)-composite of mortality, myocardial infarction, stent thrombosis, target vessel revascularisation, and stroke. RESULTS: RT recipients were younger than dialysis and patients with CKD (61±10 vs 68±12 vs 78±8.2 years, p<0.001). Patients with RT less frequently had severe left ventricular dysfunction compared with dialysis and CKD groups (6.7% vs 14% and 8.5%); however more, often presented with acute coronary syndrome (58% vs 52% and 48%), especially STEMI (all p<0.001). Patients with RT and CKD had lower rates of 30-day MACCE (4.4% and 6.8% vs 11.6%, p<0.001) than the dialysis group. Three-year survival was similar between RT and CKD groups, however was lower in the dialysis group (80% and 83% vs 60%, p<0.001). After adjustment, dialysis was an independent predictor of 30-day MACCE (odds ratio [OR] 1.90, 95% confidence interval [CI] 1.44‒2.50, p<0.001), however RT was not (OR 0.91, CI 0.42‒1.96, p=0.802). Both RT (hazard ratio [HR] 2.07, CI 1.46‒2.95, p<0.001) and dialysis (HR 1.35, CI 1.02‒1.80, p=0.036) heightened the hazard of long-term mortality. CONCLUSIONS: RT recipients have more favourable clinical outcomes following PCI compared with patients on dialysis. However, despite having similar short-term outcomes to patients with CKD, the hazard of long-term mortality is significantly greater for RT recipients.

No-Reflow Prediction in Acute Coronary Syndrome During Percutaneous Coronary Intervention: The NORPACS Risk Score.

BACKGROUND: Suboptimal coronary reperfusion (no reflow) is common in acute coronary syndrome percutaneous coronary intervention (PCI) and is associated with poor outcomes. We aimed to develop and externally validate a clinical risk score for angiographic no reflow for use following angiography and before PCI. METHODS: We developed and externally validated a logistic regression model for prediction of no reflow among adult patients undergoing PCI for acute coronary syndrome using data from the Melbourne Interventional Group PCI registry (2005-2020; development cohort) and the British Cardiovascular Interventional Society PCI registry (2006-2020; external validation cohort). RESULTS: A total of 30 561 patients (mean age, 64.1 years; 24% women) were included in the Melbourne Interventional Group development cohort and 440 256 patients (mean age, 64.9 years; 27% women) in the British Cardiovascular Interventional Society external validation cohort. The primary outcome (no reflow) occurred in 4.1% (1249 patients) and 9.4% (41 222 patients) of the development and validation cohorts, respectively. From 33 candidate predictor variables, 6 final variables were selected by an adaptive least absolute shrinkage and selection operator regression model for inclusion (cardiogenic shock, ST-segment-elevation myocardial infarction with symptom onset >195 minutes pre-PCI, estimated stent length ≥20 mm, vessel diameter <2.5 mm, pre-PCI Thrombolysis in Myocardial Infarction flow <3, and lesion location). Model discrimination was very good (development C statistic, 0.808; validation C statistic, 0.741) with excellent calibration. Patients with a score of ≥8 points had a 22% and 27% risk of no reflow in the development and validation cohorts, respectively. CONCLUSIONS: The no-reflow prediction in acute coronary syndrome risk score is a simple count-based scoring system based on 6 parameters available before PCI to predict the risk of no reflow. This score could be useful in guiding preventative treatment and future trials.

Associations Between Metabolic Syndrome and Long-Term Mortality in Patients who underwent Percutaneous Coronary Intervention: An Australian Cohort Analysis.

Metabolic syndrome (MetS) provides significant risk for coronary disease, however long-term prognosis after percutaneous coronary intervention (PCI) has been understudied. We assessed the prevalence and outcomes of patients with MetS from an Australian PCI cohort. We retrospectively examined data from the Melbourne Interventional Group multicenter PCI registry using a modified definition for MetS including ≥3 of the following: hypertension, diabetes mellitus, dyslipidemia, and body mass index ≥30 kg/m2. Thirty-day outcomes and long-term mortality were compared with patients without MetS. Cox regression methods were used to assess the multivariable effect of MetS on long-term mortality. Of 41,146 patients, 12,228 (34%) had MetS. Patients with MetS experienced greater 30-day myocardial infarction (2.2% vs 1.8%, p = 0.013), whereas patients without MetS had a trend for greater 30-day mortality (3.0% vs 3.4%, p = 0.051) and greater in-hospital major bleeding (1.7% vs 2.4%, p <0.001). After a median follow-up of 5.62 years (Q1 2.03, Q3 8.89), patients with MetS experienced greater mortality (24% vs 19%, p <0.001). After adjustment, MetS was not an independent predictor of long-term mortality (hazard ratio 0.95 confidence interval 0.86 to 1.05, p = 0.35). In sensitivity analyses, MetS-Diabetic patients had the highest, and MetS-NonDiabetic obese patients had the lowest long-term mortality. One in 3 patients who underwent all-comer PCI presented with MetS and experienced greater long-term mortality compared with others. However, this association was lost after adjustment for baseline confounders, highlighting that MetS is a marker of risk after PCI. Our findings support the obesity paradox and confirm robust associations between diabetes mellitus and long-term mortality.

Comparison of Characteristics and Outcomes in Patients With Acute Decompensated Heart Failure Admitted Under General Medicine and Cardiology Units.

BACKGROUND: Acute decompensated heart failure (ADHF) is a leading cause of cardiovascular disease hospitalisations associated with significant morbidity and mortality. In hospitals, HF patients are typically managed by cardiology or physician teams, with differences in patient demographics and clinical outcomes. This study utilises contemporary HF registry data to compare patient characteristics and outcomes in those with ADHF admitted into General Medicine and Cardiology units. METHODS: The Victorian Cardiac Outcomes Registry was utilised to identify patients hospitalised with ADHF 30-day period in each of four consecutive years. We compared patient characteristics, pharmacological management and outpatient follow-up of patients admitted to General Medicine and Cardiology units. Primary outcome measures included in-hospital mortality, 30-day readmission, and 30-day mortality. RESULTS: Between 2014 and 2017, a total of 1,253 patients with ADHF admissions were registered, with 53% admitted in General Medicine units and 47% in Cardiology units. General Medicine patients were more likely to be older (82 vs 71 years; p<0.001), female (51% vs 34%; p<0.001), and have higher prevalence of comorbidities and preserved left ventricular function (p<0.001). There were no differences in primary outcome measures between General Medicine and Cardiology in terms of: in-hospital mortality (5.0% vs 3.9%; p=0.35), 30-day readmission (23.4% vs 23.6%; p=0.93), and 30-day mortality (10.0% vs 8.0%; p=0.21). CONCLUSIONS: Hospitalised patients with HF continue to have high mortality and rehospitalisation rates. The choice of treatment by General Medicine or Cardiology units, based on the particular medical profile and individual needs of the patients, provides equivalent outcomes.

Electrocardiographic patterns and clinical outcomes of acute coronary syndrome cardiogenic shock in patients undergoing percutaneous coronary intervention - A propensity score analysis.

OBJECTIVES: To determine the influence of presenting electrocardiographic (ECG) changes on prognosis in acute coronary syndrome cardiogenic shock (ACS-CS) patients undergoing percutaneous coronary angiography (PCI). BACKGROUND: The effect of initial ECG changes such as ST-elevation myocardial infarction (STEMI) versus non-STEMI among patients ACS-CS on prognosis remains unclear. METHODS: We analysed data from consecutive patients with ACS-CS enrolled in the Victorian Cardiac Outcomes registry between 2014 and 2020. Inverse probability of treatment weighting analysis (IPTW) was used to assess the effect of ECG changes on 30-day mortality. RESULTS: Of 1564 patients with ACS-CS who underwent PCI, 161 had non-STEMI and 1403 had STEMI on ECG. The mean age was 66 ± 13 years, and 74 % (1152) were males. Patients with non-STEMI compared to STEMI were older (70 ± 12 vs 65 ± 13 years), had higher rates of diabetes (34 % vs 21 %), prior coronary artery bypass graft surgery (14 % vs 3.3 %), peripheral arterial disease (10.6 % vs 4.1 %, p < 0.01), and lower baseline eGFR (53.8 [37.1, 75.4] vs 65.3 [46.3, 87.8] ml/min/1.73m2), all p ≤ 0.01. Non-STEMI patients were more likely to have a culprit left circumflex artery (29 % vs 20 %) and more often underwent multivessel percutaneous coronary intervention (30 % vs 20 %) but had lower rates of out-of-hospital cardiac arrest (21 % vs 39 %), all p ≤ 0.01. Propensity score analysis with IPTW confirmed that non-STEMI ECG was associated with lower odds for 30-day all-cause mortality (OR 0.47 [0.32, 0.69], p < 0.001), and 30-day major adverse cardiovascular and cerebrovascular events (OR 0.48 [0.33, 0.70]). CONCLUSIONS: In patients undergoing PCI, Non-STEMI as compared to STEMI on index ECG was associated with approximately half the relative risk of both 30-day mortality and 30-day MACCE and could be a useful variable to integrate in ACS-CS risk scores.

Multimorbidity impacts cardiovascular disease risk following percutaneous coronary intervention: latent class analysis of the Melbourne Interventional Group (MIG) registry.

BACKGROUND: Multimorbidity is strongly associated with disability or functional decline, poor quality of life and high consumption of health care services. This study aimed (1) To identify patterns of multimorbidity among patients undergoing first recorded percutaneous coronary intervention (PCI); (2) To explore the association between the identified patterns of multimorbidity on length of hospital stay, 30-day and 12- month risk of major adverse cardiac and cerebrovascular events (MACCE) after PCI. METHODS: A retrospective cohort study of the Melbourne Interventional Group (MIG) registry. This study included 14,025 participants who underwent their first PCI from 2005 to 2015 in Victoria, Australia. Based on a probabilistic modelling approach, Latent class analysis was adopted to classify clusters of people who shared similar combinations and magnitude of the comorbidity of interest. Logistic regression models were used to estimate odd ratios and 95% confidence interval (CI) for the 30-day and 12-month MACCE. RESULTS: More than two-thirds of patients had multimorbidity, with the most prevalent conditions being hypertension (59%) and dyslipidaemia (60%). Four distinctive multimorbidity clusters were identified each with significant associations for higher risk of 30-day and 12-month MACCE. The cluster B had the highest risk of 30-day MACCE event that was characterised by a high prevalence of reduced estimated glomerular filtration rate (92%), hypertension (73%) and reduced ejection fraction (EF) (57%). The cluster C, characterised by a high prevalence of hypertension (94%), dyslipidaemia (88%), reduced eGFR (87%), diabetes (73%) and reduced EF (65%) had the highest risk of 12-month MACCE and highest length of hospital stay. CONCLUSION: Hypertension and dyslipidaemia are prevalent in at least four in ten patients undergoing coronary angioplasty. This study showed that clusters of patients with multimorbidity had significantly different risk of 30-day and 12-month MACCE after PCI. This suggests the necessity for treatment approaches that are more personalised and customised to enhance patient outcomes and the quality of care delivered to patients in various comorbidity clusters. These results should be validated in a prospective cohort and to evaluate the potential impacts of these clusters on the prevention of MACCE after PCI.

Real-world long-term survival after non-emergent percutaneous coronary intervention to unprotected left main coronary artery - From the Melbourne Interventional Group (MIG) registry.

BACKGROUND: Current evidence suggests that percutaneous coronary intervention for unprotected left main coronary artery disease (LMPCI) in selected patients is a safe alternative to coronary artery bypass grafting. However, real-world long-term survival data is limited. METHODS: We analyzed 24,644 patients from the MIG (Melbourne Interventional Group) registry between 2005 and 2020. We compared baseline clinical and procedural characteristics, in-hospital and 30-day outcomes, and long-term survival between unprotected LMPCI and non-LMPCI among patients without ST-segment elevation myocardial infarction, cardiogenic shock, or cardiac arrest. RESULTS: Unprotected LMPCI patients (n = 185) were significantly older (mean age 72.0 vs. 64.6 years, p < 0.001), had higher prevalence of impaired ejection fraction (EF <50 %; 27.3 % vs. 14.9 %, p < 0.001) and lower estimated glomerular filtration rate < 60 ml/min/1.73m2 (40.9 % vs. 21.5 %, p < 0.001), and had greater use of intravascular ultrasound (21 % vs. 1 %, p < 0.001) and drug-eluting stents (p < 0.001). LMPCI was associated with longer hospital stay (4 days vs. 2 days, p < 0.001). There was no significant difference in other in-hospital outcomes, 30-day mortality (0.6 % vs. 0.6 %, p = 0.90), and major adverse cardiac events (1.7 % vs. 3 %, p = 0.28). Although the unadjusted Kaplan-Meier survival to 8 years was significantly less with LMPCI compared to non-LMPCI (p < 0.01), LMPCI was not a predictor of long-term survival up to 8 years after Cox regression analysis (HR 0.67, 95 % CI 0.40-1.13, p = 0.13). CONCLUSION: In this study, non-emergent unprotected LMPCI was uncommonly performed, and IVUS was underutilized. Despite greater co-morbidities, LMPCI patients had comparable 30-day outcomes to non-LMPCI, and LMPCI was not an independent predictor of long-term mortality.

Sex Differences in Pharmacotherapy and Long-Term Outcomes in Patients With Ischaemic Heart Disease and Comorbid Left Ventricular Dysfunction.

BACKGROUND: Left ventricular (LV) dysfunction and ischaemic heart disease (IHD) are common among women. However, women tend to present later and are less likely to receive guideline-directed medical therapy (GDMT) compared with men. METHODS: We analysed prospectively collected data (2005-2018) from a multicentre registry on GDMT 30 days after percutaneous coronary intervention in 13,015 patients with LV ejection fraction <50%. Guideline-directed medical therapy was defined as beta blocker, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker±mineralocorticoid receptor antagonist. Long-term mortality was determined by linkage with the Australian National Death Index. RESULTS: Women represented 20% (2,634) of the total cohort. Mean age was 65±12 years. Women were on average >5 years, with higher body mass index and higher rates of hypertension, diabetes, renal dysfunction, prior stroke, and rheumatoid arthritis. Guideline-directed medical therapy was similar between sexes (73% vs 72%; p=0.58), although women were less likely to be on an angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (80% vs 82%; p=0.02). Women were less likely to be on statin therapy (p<0.001) or a second antiplatelet agent (p=0.007). Women had higher unadjusted long-term mortality (25% vs 19%; p<0.001); however, there were no differences in long-term mortality between sexes on adjusted analysis (hazard ratio 0.99; 95% confidence interval 0.87-1.14; p=0.94). CONCLUSIONS: Rates of GDMT for LV dysfunction were high and similar between sexes; however, women were less likely to be on appropriate IHD secondary prevention. The increased unadjusted long-term mortality in women was attenuated in adjusted analysis, which highlights the need for optimisation of baseline risk to improve long-term outcomes of women with IHD and comorbid LV dysfunction.

Natural History and Clinical Outcomes After ST-Segment Elevation Myocardial Infarction Without Stent Insertion.

After restoration of coronary perfusion in patients presenting with ST-segment elevation myocardial infarction (STEMI), discrete severe stenotic coronary lesions are not always apparent. There remains ambiguity whether drug-eluting stent (DES) insertion or initial medical management is best practice. We sought to assess short-term clinical outcomes in patients presenting with STEMI without initial stent insertion. Patients who underwent percutaneous coronary intervention for STEMI between 2014 and 2020 were prospectively enrolled and assessed for inclusion. Patients presenting with in-stent restenosis or stent thrombosis, or who did not survive to hospital discharge were excluded. Of 13,871 patients presenting, 456 (3.3%) were treated without initial stenting. These patients were older than those treated with DES (66.1 ± 13.6 vs 62.3 ± 12.4 years, p <0.001), had higher rates of diabetes (23.5% vs 16.0%, p <0.001) and previous revascularization with either percutaneous coronary intervention (14.0% vs 7.3%, p <0.001) or coronary artery bypass graft (3.5% vs 1.8%, p = 0.008). Thirty-day mortality was elevated in patients treated without stenting compared to those receiving DES (4.2% vs 0.9%, p <0.001), as were rates of myocardial infarction (1.3% vs 0.5%, p = 0.026) and major adverse cardiac events (10.5% vs 2.4%, p <0.001). After propensity matching, a trend toward increased mortality remained (4.2% vs 2.0%, p = 0.055). In conclusion, a no-stenting initial strategy, compared with DES insertion, is associated with increased 30-day mortality in those presenting with STEMI without severe stenosis. These data suggest when appropriate, current-generation DES insertion should be undertaken.

Impact of Preprocedural Diastolic Blood Pressure on Outcomes in Patients Undergoing Percutaneous Coronary Intervention.

BACKGROUND: Recent US guidelines recommend lower blood pressure (BP) targets in hypertension, but aggressive lowering of diastolic BP (DBP) can occur at the expense of myocardial perfusion, particularly in the presence of coronary artery disease. We sought to establish the long-term impact of low DBP on mortality among patients undergoing percutaneous coronary intervention with well-controlled systolic BP. METHODS: We analyzed data from 12 965 patients undergoing percutaneous coronary intervention between 2009 and 2018 from the Melbourne Interventional Group registry who had a preprocedural systolic BP of ≤140 mm Hg. Patients with ST-elevation myocardial infarction, cardiogenic shock, and out-of-hospital arrest were excluded. Patients were stratified into 5 groups according to preprocedural DBP: <50, 50 to 59, 60 to 69, 70 to 79, and ≥80 mm Hg. The primary outcome was long-term, all-cause mortality. Mortality data were derived from the Australian National Death Index. RESULTS: Patients with DBP<50 mm Hg were older with higher rates of diabetes, renal impairment, prior myocardial infarction, left ventricular dysfunction, peripheral and cerebrovascular disease (all P<0.001). Patients with DBP<50 mm Hg had higher 30-day (2.5% versus 0.7% for the other 4 quintiles; P<0.0001) and long-term mortality (median, 3.6 years; follow-up, 29% versus 11%; P<0.0001). Cox-regression analysis revealed that DBP<50 mm Hg was an independent predictor of long-term mortality (hazard ratio [HR], 1.55 [95% CI, 1.20-2.00]; P=0.001). CONCLUSIONS: In patients with well-controlled systolic BP undergoing percutaneous coronary intervention, low DBP (<50 mm Hg) is an independent predictor of long-term mortality.

Effect of Concomitant Cardiac Arrest on Outcomes in Patients With Acute Coronary Syndrome-Related Cardiogenic Shock.

Patients with acute coronary syndrome (ACS)-related cardiogenic shock (CS) with or without concomitant CA may have disparate prognoses. We compared clinical characteristics and outcomes of patients with CS secondary to ACS with and without cardiac arrest (CA). Between 2014 and 2020, 1,573 patients with ACS-related CS with or without CA who underwent percutaneous coronary intervention enrolled in a multicenter Australian registry were analyzed. Primary outcome was 30-day major adverse cardiovascular and cerebrovascular events (MACCE) (composite of mortality, myocardial infarction, stent thrombosis, target vessel revascularization and stroke). Long-term mortality was obtained through linkage to the National Death Index. Compared with the no-CA group (n = 769, 49%), the CA group (n = 804, 51%) was younger (62 vs 69 years, p <0.001) and had fewer comorbidities. Patients with CA more frequently had ST-elevation myocardial infarction (92% vs 86%), occluded left anterior descending artery (43% vs 33%), and severe preprocedural renal impairment (49% vs 42%) (all p <0.001). CA increased risk of 30-day MACCE by 45% (odds ratio 1.45, 95% confidence interval 1.05 to 2.00, p = 0.024) after adjustment. CA group had higher 30-day MACCE (55% vs 42%, p <0.001) and mortality (52% vs 37%, p <0.001). Three-year survival was lower for CA compared with no-CA patients (43% vs 52%, p <0.001). In Cox regression, CS with CA was associated with a trend toward greater long-term mortality hazard (hazard ratio 1.19, 95% confidence interval 1.00 to 1.41, p = 0.055). In conclusion, concomitant CA among patients with ACS-related CS conferred a particularly heightened short-term risk with a diminishing legacy effect over time for mortality. CS survivors continue to exhibit high sustained long-term mortality hazard regardless of CA status.

Estimating the cost-effectiveness and return on investment of the Victorian Cardiac Outcomes Registry in Australia: a minimum threshold analysis.

OBJECTIVES: We sought to establish the minimum level of clinical benefit attributable to the Victorian Cardiac Outcomes Registry (VCOR) for the registry to be cost-effective. DESIGN: A modelled cost-effectiveness study of VCOR was conducted from the Australian healthcare system and societal perspectives. SETTING: Observed deaths and costs attributed to coronary heart disease (CHD) over a 5-year period (2014-2018) were compared with deaths and costs arising from a hypothetical situation which assumed that VCOR did not exist. Data from the Australian Bureau of Statistics and published sources were used to construct a decision analytic life table model to simulate the follow-up of Victorians aged ≥25 years for 5 years, or until death. The assumed contribution of VCOR to the proportional change in CHD mortality trend observed over the study period was varied to quantify the minimum level of clinical benefits required for the registry to be cost-effective. The marginal costs of VCOR operation and years of life saved (YoLS) were estimated. PRIMARY OUTCOME MEASURES: The return on investment (ROI) ratio and the incremental cost-effectiveness ratio (ICER). RESULTS: The minimum proportional change in CHD mortality attributed to VCOR required for the registry to be considered cost-effective was 0.125%. Assuming this clinical benefit, a net return of $A4.30 for every dollar invested in VCOR was estimated (ROI ratio over 5 years: 4.3 (95% CI 3.6 to 5.0)). The ICER estimated for VCOR was $A49 616 (95% CI $A42 228 to $A59 608) per YoLS. Sensitivity analyses found that the model was sensitive to the time horizon assumed and the extent of registry contribution to CHD mortality trends. CONCLUSIONS: VCOR is likely cost-effective and represents a sound investment for the Victorian healthcare system. Our evaluation highlights the value of clinical quality registries in Australia.

Registry randomised trials: a methodological perspective.

Registry randomised clinical trials (RRCTs) have the potential to provide pragmatic answers to important clinical questions. RRCTs can be embedded into large population-based registries or smaller single site registries to provide timely answers at a reduced cost compared with traditional randomised controlled trials. RRCTs can take a number of forms in addition to the traditional individual-level randomised trial, including parallel group trials, platform or adaptive trials, cluster randomised trials and cluster randomised stepped-wedge trials. From an implementation perspective, initially it is advantageous to embed RRCT into well-established registries as these have typically already overcome any issues with end point validation and adjudication. With advances in data linkage and data quality, RRCTs can play an important role in answering clinical questions in a pragmatic, cost-effective way.

Characteristics of Radial Artery Coronary Bypass Graft Failure and Outcomes Following Subsequent Percutaneous Coronary Intervention.

BACKGROUND: When patients with prior coronary artery bypass grafting (CABG) undergo percutaneous coronary intervention (PCI), targeting the native vessel is preferred. Studies informing such recommendations are based predominantly on saphenous vein graft (SVG) PCI. There are few data regarding arterial graft intervention, particularly to a radial artery (RA) graft. OBJECTIVES: The aim of this study was to report the characteristics of arterial graft stenoses and evaluate the feasibility of RA PCI. METHODS: This study included 2,780 consecutive patients with prior CABG undergoing PCI between 2005 and 2018 who were prospectively enrolled in the MIG (Melbourne Interventional Group) registry. Data were stratified by PCI target vessel. RA graft PCI was compared with both native vessel (native PCI) and SVG PCI. Internal mammary graft PCI data were reported. The primary outcome was 3-year mortality. RESULTS: Overall, 1,928 patients (69.4%) underwent native PCI, 716 (25.6%) SVG PCI, 86 (3.1%) RA PCI, and 50 (1.8%) internal mammary graft PCI. Compared with SVG PCI, the RA PCI cohort presented earlier after CABG, less frequently had acute coronary syndrome, and more commonly had ostial or distal anastomosis intervention (P < 0.005 for all). Compared with patients who underwent native PCI, those who underwent RA PCI were more likely to have diabetes and peripheral vascular disease (P < 0.001 for both) and to present with non-ST-segment elevation myocardial infarction (P = 0.010). The RA PCI group had no perforations or in-hospital myocardial infarctions, though no significant difference was found in periprocedural outcomes compared with either native or SVG PCI. No differences were found between RA PCI and either native or SVG PCI in 30-day outcomes or 3-year mortality. CONCLUSIONS: Presenting and lesion characteristics differed between patients undergoing arterial compared with SVG PCI, implying a varied pathogenesis of graft stenosis. RA PCI appears feasible, safe, and where anatomically suitable, may be a viable alternative to native PCI.

Predicting areas important for ecological connectivity throughout Canada.

Governments around the world have acknowledged that urgent action is needed to conserve and restore ecological connectivity to help reverse the decline of biodiversity. In this study we tested the hypothesis that functional connectivity for multiple species can be estimated across Canada using a single, upstream connectivity model. We developed a movement cost layer with cost values assigned using expert opinion to anthropogenic land cover features and natural features based on their known and assumed effects on the movement of terrestrial, non-volant fauna. We used Circuitscape to conduct an omnidirectional connectivity analysis for terrestrial landscapes, in which the potential contribution of all landscape elements to connectivity were considered and where source and destination nodes were independent of land tenure. Our resulting map of mean current density provided a seamless estimate of movement probability at a 300 m resolution across Canada. We tested predictions in our map using a variety of independently collected wildlife data. We found that GPS data for individual caribou, wolves, moose, and elk that traveled longer distances in western Canada were all significantly correlated with areas of high current densities. The frequency of moose roadkill in New Brunswick was also positively associated with current density, but our map was not able to predict areas of high road mortality for herpetofauna in southern Ontario. The results demonstrate that an upstream modelling approach can be used to characterize functional connectivity for multiple species across a large study area. Our national connectivity map can help governments in Canada prioritize land management decisions to conserve and restore connectivity at both national and regional scales.

Trends in Intra-Aortic Balloon Pump Use in Cardiogenic Shock After the SHOCK-II Trial.

Myocardial infarction complicated by cardiogenic shock (MI-CS) has a poor prognosis, even with early revascularization. Previously, intra-aortic balloon pump (IABP) use was thought to improve outcomes, but the IABP-SHOCK-II (Intra-aortic Balloon Pump in Cardiogenic Shock-II study) trial found no survival benefit. We aimed to determine the trends in IABP use in patients who underwent percutaneous intervention over time. Data were taken from patients in the Melbourne Interventional Group registry (2005 to 2018) with MI-CS who underwent percutaneous intervention. The primary outcome was the trend in IABP use over time. The secondary outcomes included 30-day mortality and major adverse cardiovascular and cerebrovascular events (MACCEs). Of the 1,110 patients with MI-CS, IABP was used in 478 patients (43%). IABP was used more in patients with left main/left anterior descending culprit lesions (62% vs 46%), lower ejection fraction (<35%; 18% vs 11%), and preprocedural inotrope use (81% vs 73%, all p <0.05). IABP use was associated with higher bleeding (18% vs 13%) and 30-day MACCE (58% vs 51%, both p <0.05). The rate of MI-CS per year increased over time; however, after 2012, there was a decrease in IABP use (p <0.001). IABP use was a predictor of 30-day MACCE (odds ratio 1.6, 95% confidence interval 1.18 to 2.29, p = 0.003). However, IABP was not associated with in-hospital, 30-day, or long-term mortality (45% vs 47%, p = 0.44; 46% vs 50%, p = 0.25; 60% vs 62%, p = 0.39). In conclusion, IABP was not associated with reduced short- or long-term mortality and was associated with increased short-term adverse events. IABP use is decreasing but is predominately used in sicker patients with greater myocardium at risk.