Pulmonary Artery Pseudoaneurysm Associated With Abandoned Epicardial Defibrillator Patch

We describe an 84-year-old man who presented with hemoptysis and acute blood loss anemia due to a pulmonary artery pseudoaneurysm (PAP). The etiology of his PAP was thought to be an abandoned epicardial defibrillator patch that was implanted at age 55. To our knowledge, PAP has never been reported as a possible complication of an abandoned epicardial defibrillator patch.

Equipment utilization in chronic total occlusion percutaneous coronary interventions: Insights from the PROGRESS-CTO registry

BACKGROUND

We examined guidewire and microcatheter utilization during chronic total occlusion (CTO) percutaneous coronary intervention (PCI).

METHODS

We examined device utilization in 2,968 CTO PCIs performed in 2,936 patients at 19 US and two international center between January 2016 and January 2019.

RESULTS

The median number of antegrade guidewires used per case declined (5 in 2016 vs 3 in 2019) and was higher in higher complexity lesions (2 in J-CTO 0 vs. 8 in J-CTO 4 or 5 score). In antegrade-only procedures, the most frequently used guidewires were the Pilot 200 (Abbott Vascular, 37%), Fielder XT (Asahi Intecc, 25%) and Gaia third (Asahi Intecc, 18%), while the most commonly used microcatheters were the Turnpike Spiral (Vascular Solutions, 18%) and Turnpike (Vascular Solutions, 16%). Compared with 2012-2015, during 2016-2019 use of novel equipment such as the Gaia guidewires and the Turnpike microcatheters led to decreased use of Confianza Pro 12 (Asahi Intecc) wire and Corsair (Asahi Intecc) family of microcatheters. In retrograde cases, the guidewires most commonly used were the Sion (44%), Pilot 200 (27%) and Fielder FC (26%), while the Corsair/Corsair Pro, Turnpike LP (Vascular Solutions) and Caravel (Asahi Intecc) were the most frequently used microcatheters for collateral crossing (29%, 26% and 22%, respectively).

CONCLUSIONS

The most commonly used guidewires during CTO PCI are polymer-jacketed guidewires and the most commonly used microcatheters are torquable microcatheters.

Efficacy of catheter-based renal denervation in the absence of antihypertensive medications (SPYRAL HTN-OFF MED Pivotal): a multicentre, randomised, sham-controlled trial

BACKGROUND

Catheter-based renal denervation has significantly reduced blood pressure in previous studies. Following a positive pilot trial, the SPYRAL HTN-OFF MED (SPYRAL Pivotal) trial was designed to assess the efficacy of renal denervation in the absence of antihypertensive medications.

METHODS

In this international, prospective, single-blinded, sham-controlled trial, done at 44 study sites in Australia, Austria, Canada, Germany, Greece, Ireland, Japan, the UK, and the USA, hypertensive patients with office systolic blood pressure of 150 mm Hg to less than 180 mm Hg were randomly assigned 1:1 to either a renal denervation or sham procedure. The primary efficacy endpoint was baseline-adjusted change in 24-h systolic blood pressure and the secondary efficacy endpoint was baseline-adjusted change in office systolic blood pressure from baseline to 3 months after the procedure. We used a Bayesian design with an informative prior, so the primary analysis combines evidence from the pilot and Pivotal trials. The primary efficacy and safety analyses were done in the intention-to-treat population. This trial is registered at ClinicalTrials.gov, NCT02439749.

FINDINGS

From June 25, 2015, to Oct 15, 2019, 331 patients were randomly assigned to either renal denervation (n=166) or a sham procedure (n=165). The primary and secondary efficacy endpoints were met, with posterior probability of superiority more than 0·999 for both. The treatment difference between the two groups for 24-h systolic blood pressure was -3·9 mm Hg (Bayesian 95% credible interval -6·2 to -1·6) and for office systolic blood pressure the difference was -6·5 mm Hg (-9·6 to -3·5). No major device-related or procedural-related safety events occurred up to 3 months.

INTERPRETATION

SPYRAL Pivotal showed the superiority of catheter-based renal denervation compared with a sham procedure to safely lower blood pressure in the absence of antihypertensive medications.

FUNDING

Medtronic.

Temporal Trends in Chronic Total Occlusion Percutaneous Coronary Interventions: Insights From the PROGRESS-CTO Registry

BACKGROUND

Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has significantly evolved in recent years.

METHODS

We compared the clinical, angiographic, and technical characteristics, as well as procedural outcomes of CTO-PCIs in a multicenter registry between the "early era" (2012-2016) and the "current era" (2017-2019).

RESULTS

Current era patients more often had stage III or IV angina compared with early era patients (71% vs 66%, respectively; P=.03) and were less likely to undergo ad hoc CTO-PCI (13% vs 16%, respectively; P=.04). The J-CTO score was slightly lower in the current era patients vs the early era patients (2.3 ± 1.4 vs 2.5 ± 1.3, respectively; P=.04). Use of antegrade wire escalation increased in the current era (92% vs 83% in the early era patients; P<.001) whereas use of retrograde crossing decreased (29% vs 39% in the early era; P<.001) and antegrade/ dissection re-entry decreased (23% vs 32% in the early era; P<.001). Technical success rates (85% in the current era vs 86% in the early era; P=.69) and procedural success rates (83% in the current era vs 85% in the early era; P=.15) were similar, whereas the incidence of in-hospital major cardiovascular events decreased in the current era (2% vs 3% in the early era; P=.04).

CONCLUSIONS

During recent years, ad hoc CTO-PCI decreased along with decreasing use of retrograde crossing and antegrade dissection and re-entry. Technical and procedural success rates remained stable, whereas the incidence of in-hospital MACE decreased.

Impact of concomitant treatment of non-chronic total occlusion lesions at the time of chronic total occlusion intervention

BACKGROUND

During chronic total occlusion (CTO) percutaneous coronary intervention (PCI), sometimes non-CTO lesions are also treated.

METHODS

We compared the clinical and procedural characteristics and outcomes of CTO PCIs with and without concomitant treatment of a non-CTO lesion in a contemporary multicenter CTO registry.

RESULTS

Of the 3598 CTO PCIs performed at 21 centers between 2012 and 2018, 814 (23%) also included PCI of at least one non-CTO lesion. Patients in whom non-CTO lesions were treated were older (65 ± 10 vs. 64 ± 10 years, p = 0.03), more likely to present with an acute coronary syndrome (32% vs. 23%, p < 0.01), and less likely to undergo PCI of a right coronary artery (RCA) CTO (46% vs. 58%, p < 0.01). The most common non-CTO lesion location was the left anterior descending artery (31%), followed by the circumflex (29%) and the RCA (25%).Combined non-CTO and CTO-PCI procedures had similar technical (88% vs. 87%, p = 0.33) and procedural (85% vs. 85%, p = 0.74) success and major in-hospital complication rates (3.4% vs. 2.7%, p = 0.23), but had longer procedure duration (131 [88, 201] vs. 117 [75, 179] minutes, p < 0.01), higher patient air kerma radiation dose (3.0 [1.9, 4.8] vs. 2.8 [1.5, 4.6] Gray, p < 0.01) and larger contrast volume (300 [220, 380] vs. 250 [180, 350] ml, p < 0.01).

CONCLUSIONS

Combined CTO PCI with PCI of non-CTO lesions is associated with similar success and major in-hospital complication rates compared with cases in which only CTOs were treated, but requires longer procedure duration and higher radiation dose and contrast volume.

The Impact of Peripheral Artery Disease in Chronic Total Occlusion Percutaneous Coronary Intervention (Insights From PROGRESS-CTO Registry)

The impact of peripheral artery disease (PAD) in patients undergoing chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study. We reviewed 3999 CTO PCIs performed in 3914 patients between 2012 and 2018 at 25 centers, 14% of whom had a history of PAD. We compared the clinical and angiographic characteristics and procedural outcomes of patients with versus without history of PAD. Patients with PAD were older (67 ± 9 vs 64 ± 10 years, P < .001) and had a higher prevalence of cardiovascular risk factors. They also had more complex lesions as illustrated by higher Japanese CTO score (2.7 ± 1.2 vs 2.4 ± 1.3, P < .001). In patients with PAD, the final crossing technique was less often antegrade wire escalation (40% vs 51%, P < .001) and more often the retrograde approach (23 vs 20%, P < .001) and antegrade dissection/reentry (20% vs 16%, P < .001). Technical success was similar between the 2 study groups (84% vs 87%, P = .127), but procedural success was lower for patients with PAD (81% vs 85%, P = .015). The incidence of in-hospital major adverse cardiac events was higher among patients with PAD (3% vs 2%, P = .046). In conclusion, patients with PAD undergoing CTO PCI have more comorbidities, more complex lesions, and lower procedural success.

Creation and annihilation of topological meron pairs in in-plane magnetized films

Merons which are topologically equivalent to one-half of skyrmions can exist only in pairs or groups in two-dimensional (2D) ferromagnetic (FM) systems. The recent discovery of meron lattice in chiral magnet Co₈Zn₉Mn₃ raises the immediate challenging question that whether a single meron pair, which is the most fundamental topological structure in any 2D meron systems, can be created and stabilized in a continuous FM film? Utilizing winding number conservation, we develop a new method to create and stabilize a single pair of merons in a continuous Py film by local vortex imprinting from a Co disk. By observing the created meron pair directly within a magnetic field, we determine its topological structure unambiguously and explore the topological effect in its creation and annihilation processes. Our work opens a pathway towards developing and controlling topological structures in general magnetic systems without the restriction of perpendicular anisotropy and Dzyaloshinskii–Moriya interaction.

A meron is one half of a skyrmion but whether a single meron pair can be created and stabilized remains a challenging question. Here, Gao et al. develop a method to create and stabilize individual pairs of merons in a continuous Py film by local vortex imprinting from Co disks.

An innovative magnetic state generator using machine learning techniques

We propose a new efficient algorithm to simulate magnetic structures numerically. It contains a generative model using a complex-valued neural network to generate k-space information. The output information is hermitized and transformed into real-space spin configurations through an inverse fast Fourier transform. The Adam version of stochastic gradient descent is used to minimize the magnetic energy, which is the cost of our algorithm. The algorithm provides the proper ground spin configurations with outstanding performance. In model cases, the algorithm was successfully applied to solve the spin configurations of magnetic chiral structures. The results also showed that a magnetic long-range order could be obtained regardless of the total simulation system size.

Thermostable xylanase derived from Trichoderma citrinoviride increases growth performance and non-starch polysaccharide degradation in broiler chickens

1. The aim of this trial was to determine the optimal supplementation level of a xylanase enzyme from Trichoderma citrinoviride on growth performance, apparent ileal and total tract nutrient retention, intestinal morphology, and intestinal concentration of volatile fatty acids in broiler chickens.2. A total of 600 broiler chickens (Ross 308) of mixed sex were randomly allotted to four treatments, on the basis of similar body weight. The dietary treatments were made from a corn-wheat-soy based diet supplemented with either 0, 3750, 7500, or 11 250 XU/kg xylanase and were fed to 32 d of age.3. A linear response to increasing dietary xylanase was demonstrated for overall weight gain (P < 0.05) and feed conversion ratio (P < 0.05). The apparent total tract digestibility of dry matter and gross energy, and the coefficient of apparent ileal digestibility (CIAD) of N and soluble non-starch polysaccharides were linearly improved when xylanase was added to the diet (P < 0.05). Moreover, a linear increase (P < 0.05) was observed in the CIAD of Arg, Lys, and Try with increasing dietary levels of xylanase.4. The viscosity of digesta in ileum was linearly decreased when dietary xylanase level increased (P < 0.05).5. An increase in villus height of the duodenum and jejunum were observed with increasing dietary levels of xylanase (linear, P < 0.05).6. Overall, the results showed that the effects of dietary xylanase supplementation on broiler performance was determined through effects on nutrient availability and intestinal morphology.

Smeloff-Cutter Mechanical Prosthesis in the Aortic Position for 49 Years

We describe a 76-year-old male physician who at age 27 underwent replacement of his stenotic aortic valve with a Smeloff-Cutter mechanical prosthesis which functioned normally for 49 years. He died of a noncardiac condition. A normally functioning substitute cardiac valve for this length of time has not been previously reported (1).

Evaluating Tissue Contrast and Detecting White Matter Injury in the Infant Brain: A Comparison Study of Synthetic Phase-Sensitive Inversion Recovery

BACKGROUND AND PURPOSE

Synthetic MR imaging enables the acquisition of phase-sensitive inversion recovery images. The aim of this study was to compare the image quality of synthetic phase-sensitive inversion recovery with that of other sequences in infants.

MATERIALS AND METHODS

Brain MR imaging with 3D T1-weighted fast-spoiled gradient recalled, synthetic T1WI, and synthetic phase-sensitive inversion recovery of 91 infants was compared. Contrast between unmyelinated WM and myelinated WM and between unmyelinated WM and cortical GM was calculated. Qualitative evaluation of image quality and myelination degree was performed. In infants with punctate white matter injuries, the number of lesions was compared.

RESULTS

The contrast between unmyelinated WM and myelinated WM was higher in synthetic phase-sensitive inversion recovery compared with fast-spoiled gradient recalled or synthetic T1WI (P < .001). Compared with synthetic T1WI, synthetic phase-sensitive inversion recovery showed higher gray-white matter differentiation (P < .001) and myelination degree in the cerebellar peduncle (P < .001). The number of detected punctate white matter injuries decreased with synthetic phase-sensitive inversion recovery compared with fast-spoiled gradient recalled sequences (1.2 ± 3.2 versus 3.4 ± 3.6, P = .001).

CONCLUSIONS

Synthetic phase-sensitive inversion recovery has the potential to improve tissue contrast and image quality in the brain MR imaging of infants. However, we have to be aware that synthetic phase-sensitive inversion recovery has limited value when assessing punctate white matter injuries compared with 3D fast-spoiled gradient recalled imaging.

First and recurrent events after percutaneous coronary intervention: implications for survival analyses

Objectives. Using composite endpoints and/or only first events in clinical research result in information loss and alternative statistical methods which incorporate recurrent event data exist. We compared information-loss under traditional analyses to alternative models. Design. We conducted a retrospective analysis of patients who underwent percutaneous coronary intervention (Jan2010-Dec2014) and constructed Cox models for a composite endpoint (readmission/death), a shared frailty model for recurrent events, and a joint frailty (JF) model to simultaneously account for recurrent and terminal events and evaluated the impact of heart failure (HF) on the outcome. Results. Among 4901 patients, 2047(41.8%) experienced a readmission or death within 1 year. Of those with recurrent events, 60% had ≥1 readmission and 6% had >4; a total of 121(2.5%) patients died during follow-up. The presence of HF conferred an adjusted Hazard ratio (HR) of 1.32 (95% CI: 1.18-1.47, p < .001) for the risk of composite endpoint (Cox model), 1.44 (95% CI: 1.36-1.52, p < .001) in the frailty model, and 1.34 (95% CI:1.22-1.46, p < .001) in the JF model. However, HF was not associated with death (HR 0.87, 95% CI: 0.52-1.48, p = .61) in the JF model. Conclusions. Using a composite endpoint and/or only the first event yields substantial loss of information, as many individuals endure >1 event. JF models reduce bias by simultaneously providing event-specific HRs for recurrent and terminal events.

Left Main Chronic Total Occlusion Percutaneous Coronary Intervention: A Case Series

BACKGROUND

Left main coronary artery (LMCA) chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has received limited study.

METHODS

We reviewed 4436 CTO-PCIs performed in 4340 patients between 2012 and 2018 at 25 sites. LMCA-CTO-PCI was performed in 20 cases (0.45%). We examined the clinical and angiographic characteristics and procedural outcomes of these cases.

RESULTS

Mean patient age was 68 ± 11 years and 65% were men. Most patients (85%) had undergone prior coronary artery bypass graft surgery and had a protected left main. Mean J-CTO score was 2.7 ± 1.3, mean PROGRESS-CTO score was 1.3 ± 1.1, and mean PROGRESS-CTO Complications score was 3.8 ± 1.9. Antegrade-wire escalation was the most common successful crossing strategy (50%), followed by retrograde crossing (30%) and antegrade dissection/re-entry (10%). Technical and procedural success rates were both 85%. One patient with failed LMCA-CTO-PCI had periprocedural myocardial infarction. Median procedure time was 178 minutes (interquartile range [IQR], 123-250 minutes), median contrast volume was 190 mL (IQR, 133-339 mL), and patient air kerma radiation dose was 2.6 Gray (IQR, 1.3-3.9 Gray).

CONCLUSIONS

LMCA-CTO-PCI is infrequent, is performed mostly in patients with prior coronary artery bypass graft surgery, and is associated with good procedural outcomes.

Combined surgical approach to intralabyrinthine schwannoma

INTRODUCTION

Intralabyrinthine schwannoma (ILS) is a tumor originating from the Schwann cells in the inner ear. Various surgical approaches can be used for the resection of ILS. The aim of this report is to describe a case involving a 60-year-old man who was treated successfully with a combined surgical approach.

CASE REPORT

The patient underwent a combined microscopic (transmastoid labyrinthectomy) and endoscopic procedure for surgical excision of ILS involving the vestibule and the lower half of the cochlear basal turn. The combined surgical technique enabled a complete removal of the ILS without removal of the unaffected cochlea as well as the external auditory canal. Besides additional exclusion of the middle ear, blind-sac closure of the external auditory canal and cavity obliteration were avoided. No postoperative complications were observed.

DISCUSSION

A combined microscopic and endoscopic approach to surgery enables removal of the ILS involving the vestibule and the lower half of the cochlear basal turn while helping to reduce surgical radicality.

Papillary fibroelastoma in the left atrium

Described herein is a 71-year-old woman with previous angina pectoris who suddenly developed slurred speech and right-arm weakness. She was found to have significant coronary narrowing, a small mass in the left atrium attached to the endocardium near the orifice of the appendage, and multifocal punctate cerebral lesions in the distribution of the left middle cerebral artery. The left atrial mass was excised and confirmed to be a papillary fibroelastoma. Coronary bypass was also performed. It is believed that fibrin thrombus developed within the fronds of the fibroelastoma and embolized to the brain. Such lesions in the left atrium are exceedingly uncommon. She had no further emboli events.

A Novel Collateral Imaging Method Derived from Time-Resolved Dynamic Contrast-Enhanced MR Angiography in Acute Ischemic Stroke: A Pilot Study

BACKGROUND AND PURPOSE

Assessment of the collateral status has been emphasized for appropriate treatment decisions in patients with acute ischemic stroke. The purpose of this study was to introduce a multiphase MRA collateral imaging method (collateral map) derived from time-resolved dynamic contrast-enhanced MRA and to verify the value of the multiphase MRA collateral map in acute ischemic stroke by comparing it with the multiphase collateral imaging method (MRP collateral map) derived from dynamic susceptibility contrast-enhanced MR perfusion.

MATERIALS AND METHODS

From a prospectively maintained registry of acute ischemic stroke, MR imaging data of patients with acute ischemic stroke caused by steno-occlusive lesions of the unilateral ICA and/or the M1 segment of the MCA were analyzed. We generated collateral maps using dynamic signals from dynamic contrast-enhanced MRA and DSC-MRP using a Matlab-based in-house program and graded the collateral scores of the multiphase MRA collateral map and the MRP collateral map independently. Interobserver reliabilities and intermethod agreement between both collateral maps for collateral grading were tested.

RESULTS

Seventy-one paired multiphase MRA and MRP collateral maps from 67 patients were analyzed. The interobserver reliabilities for collateral grading using multiphase MRA or MRP collateral maps were excellent (weighted κ = 0.964 and 0.956, respectively). The agreement between both collateral maps was also excellent (weighted κ = 0.884; 95% confidence interval, 0.819-0.949).

CONCLUSIONS

We demonstrated that the dynamic signals of dynamic contrast-enhanced MRA could be used to generate multiphase collateral images and showed the possibility of the multiphase MRA collateral map as a useful collateral imaging method in acute ischemic stroke.

Frequency and Outcomes of Ad Hoc Versus Planned Chronic Total Occlusion Percutaneous Coronary Intervention: Multicenter Experience

BACKGROUND

For patients needing coronary chronic total occlusion (CTO) percutaneous coronary intervention (PCI), a planned, staged intervention has been recommended by experts. Ad hoc CTO-PCI, however, occurs in practice.

METHODS

Observational, contemporary, multicenter, international registry. Our goals were to determine the frequency, characteristics, procedural techniques, and outcomes of patients who underwent ad hoc vs planned CTO-PCI.

RESULTS

Among 2282 patients who underwent CTO-PCI between 2012 and 2017, 318 (14%) were ad hoc. Patients undergoing ad hoc CTO-PCI had lower J-CTO, PROGRESS CTO, and PROGRESS Complications scores. Antegrade-wire escalation was used more often in ad hoc PCI (96% vs 81%; P<.001), whereas antegrade-dissection re-entry (22% vs 32%) and retrograde approaches (14% vs 38%) were more common in planned PCI (P<.001). There was no difference in ad hoc vs planned PCI in technical (85% vs 86%) and procedural success (84% vs 84%). In-hospital major adverse cardiac events (MACE) were more common in patients who underwent planned procedures (0.6% vs 2.9%; P=.02). Multivariable analyses showed that ad hoc CTO-PCI was not associated with technical success or MACE.

CONCLUSIONS

Ad hoc CTO-PCI occurs more commonly in less complex lesions and is associated with similarly high success rates as planned CTO-PCI in lower J-CTO score lesions, suggesting that ad hoc CTO-PCI may be an acceptable option for experienced hybrid operators in carefully selected cases. Complex cases, as quantified by the J-CTO score, have a higher in-hospital MACE rate and should preferably be performed following proper planning and preparation.

Usefulness of Atherectomy in Chronic Total Occlusion Interventions (from the PROGRESS-CTO Registry)

There is limited data on the use of atherectomy during chronic total occlusion (CTO) percutaneous coronary intervention (PCI). We compared the clinical and procedural characteristics and outcomes of CTO PCIs performed with or without atherectomy in a contemporary multicenter CTO PCI registry. Between 2012 and 2018, 3,607 CTO PCIs were performed at 21 participating centers. Atherectomy was used in 117 (3.2%) cases: rotational atherectomy in 105 cases, orbital atherectomy in 8, and both in 4 cases. Patients in whom atherectomy was used, were older (68 ± 8 vs 64 ± 10 years, p <0.0001) and had higher Japan-chronic total occlusion score (3.0 ± 1.2 vs 2.4 ± 1.3, p <0.0001). CTO PCI cases in which atherectomy was used had similar technical (91% vs 87%, p = 0.240) and procedural (90% vs 85%, p = 0.159) success and in-hospital major adverse cardiac event (4% vs 3%, p = 0.382) rates. However, atherectomy cases were associated with higher rates of donor vessel injury (4% vs 1%, p = 0.031), tamponade requiring pericardiocentesis (2.6% vs 0.4%, p = 0.012) and more often required use of a left ventricular assist device (9% vs 5%, p = 0.031). Atherectomy cases were associated with longer procedural duration (196 [141, 247] vs 119 [76, 180] minutes, p <0.0001), and higher patient air kerma radiation dose (3.6 [2.5, 5.6] vs 2.8 [1.6, 4.7] Gray, p = 0.001). In conclusion, atherectomy is currently performed in approximately 3% of CTO PCI cases and is associated with similar technical and procedural success and overall major adverse cardiac event rates, but higher risk for donor vessel injury and tamponade.

Event dependence in the analysis of cardiovascular readmissions postpercutaneous coronary intervention

Recurrent hospitalizations are common in longitudinal studies; however, many forms of cumulative event analyses assume recurrent events are independent. We explore the presence of event dependence when readmissions are spaced apart by at least 30 and 60 days. We set up a comparative framework with the assumption that patients with emergency percutaneous coronary intervention (PCI) will be at higher risk for recurrent cardiovascular readmissions than those with elective procedures. A retrospective study of patients who underwent PCI (January 2008-December 2012) with their follow-up information obtained from a regional database for hospitalization was conducted. Conditional gap time (CG), frailty gamma (FG) and conditional frailty models (CFM) were constructed to evaluate the dependence of events. Relative bias (%RB) in point estimates using CFM as the reference was calculated for comparison of the models. Among 4380 patients, emergent cases were at higher risk as compared with elective cases for recurrent events in different statistical models and time-spaced data sets, but the magnitude of HRs varied across the models (adjusted HR [95% CI]: all readmissions [unstructured data]-CG 1.16 [1.09 to 1.22], FG 1.45 [1.33 to 1.57], CFM 1.24 [1.16 to 1.32]; 30-day spaced-CG1.14 [1.08 to 1.21], FG 1.28 [1.17 to 1.39], CFM 1.17 [1.10 to 1.26]; and 60-day spaced-CG 1.14 [1.07 to 1.22], FG 1.23 [1.13 to 1.34] CFM 1.18 [1.09 to 1.26]). For all of the time-spaced readmissions, we found that the values of %RB were closer to the conditional models, suggesting that event dependence dominated the data despite attempts to create independence by increasing the space in time between admissions. Our analysis showed that independent of the intercurrent event duration, prior events have an influence on future events. Hence, event dependence should be accounted for when analyzing recurrent events and challenges contemporary methods for such analysis.