Utility of a multipurpose catheter for transvenous extraction of old broken leads: A novel technique for fragile leads.

BACKGROUND: Transvenous lead extraction has been possible since the 1980s. However, complications during lead extraction, such as the distal end fragment of the lead remaining in the myocardium or venous system and injury to the veins or heart, have been reported. OBJECTIVE: The purpose of this study was to examine our method for complete removal of a separated lead, as extraction of long-term implanted devices is difficult using standard methods and may require additional procedures. The removal of leads with inner conductor coil and lead tip separated from outer insulation, conductor coil, and proximal ring electrode using a multipurpose catheter is reported. METHODS: In total, 345 consecutive patients who underwent transvenous lead extraction (TLE) from April 2014 to March 2021 were retrospectively analyzed. Lead characteristics, device type, and indications for extraction were further analyzed in 20 patients who developed separation of the proximal ring electrode and outer conductor coil from the inner conductor and distal tip at the time of extraction. RESULTS: Extractions were performed using an excimer laser sheath laser and a Byrd polypropylene telescoping sheath (n = 15); laser, Byrd polypropylene telescoping sheath, and Evolution RL (n = 2); laser and Evolution RL (n = 3); Byrd polypropylene telescoping sheath and Evolution RL (n = 1); Byrd polypropylene telescoping sheath only (n = 4); and Evolution RL only (n = 2). Twenty-seven leads implanted for more than 10 years had lead separation. A multipurpose catheter was used to protect the fragile leads from further damage. All leads were completely extracted. CONCLUSION: All distal tip-to-proximal ring electrode separated leads were successfully removed using laser and other sheaths with the assistance of a multipurpose catheter, without any part of the leads remaining in the heart.

Usefulness of the controlled-rotation dilator sheath "Evolution RL" for extraction of old leads in two Japanese centers - An experience in use.

BACKGROUND: Transvenous lead extraction (TLE) is an established procedure for the management of cardiovascular implantable electronic devices. However, some difficulties and risks of complications still exist, especially in old and adhered leads. Evolution RL (Cook Medical, Bloomington, IN, USA) is a newly introduced device for TLE; however, no clinical results have been reported in Japan, and the results with older leads are unknown. We investigated the efficacy and safety of Evolution RL and its usefulness for old leads at two TLE centers in Japan. METHODS: A total of 27 consecutive patients who underwent lead extraction using Evolution RL at Shinshu University Hospital and Tokyo Women's Medical University Hospital from September 2017 to December 2019 were retrospectively enrolled. We examined the backgrounds of the patients and leads and investigated the efficacy and safety of the procedures. We divided the leads into two groups according to the number of years of implantation (10 years) and compared the results. RESULTS: Among the 27 patients, 20 (74.1%) were men, and the median age was 62 (14-91) years. The total number of leads was 58, and the median implantation duration was 136 months (8-448). We achieved clinical success in all patients and complete procedural success in 24 patients (88.9%). In three patients, the broken tip of the lead remained in the heart. No major complications were noted. Of the 58 leads, there were 34 leads with more than 10 years of implantation, with significantly more Evolution RLs used (94.1% vs. 54.2%, p = 0.001) and significantly higher percentages of Evolution 11Fr, 13Fr, and steady sheaths used (79.4% vs. 33.3%, p = 0.001, 52.9% vs. 16.7%, p = 0.006, and 64.7% vs. 20.8%, p = 0.001, respectively). CONCLUSIONS: In two TLE centers in Japan, Evolution RL was shown to be safe and effective, even in leads older than 10 years.

Leadless cardiac pacemaker implantations after infected pacemaker system removals in octogenarians.

BACKGROUND: Management of pacemaker (PM) infections among advanced aged patients possesses particular clinical challenges due to higher rates of concurrent cardiovascular disease and medical comorbidities. Novel leadless cardiac pacemakers (LCPs) may provide new opportunities for better management options in this population, however, there is limited data especially in Asian populations to guide the decision making. METHODS: We reviewed 11 octogenarians (median age: 86 [minimum 82-maximum 90] years; male: 73%; median body mass index (BMI): 20.1 kg/m2) who received Micra Transcatheter Pacing System (Medtronic Inc, Minneapolis, MN) implantations following transvenous lead extractions (TLEs) for PM infections. RESULTS: All patients had more than two medical comorbidities (average 3.7 comorbidities). The indications for LCP implantations were atrioventricular block in four patients, atrial fibrillation bradycardia in five, and sinus node dysfunction in two. Eight patients (73%) were bridged with temporary pacing using active fixation leads (median interval of 14.0 days), while one with severe dementia underwent a concomitant LCP implantation and TLE during the same procedure. Successful TLEs and LCP implantations were successfully accomplished in all without any complications. The median time from the TLE procedure to discharge was 22 days (minimum 7-maximum 136). All patients remained free of infections during a mean follow-up period of 17.2 ± 6.5 months. CONCLUSIONS: LCP implantations were safe and effective after removing the entire infectious PM system in all octogenarians. The novel LCP technology may offer an alternative option for considering a re-implantation strategy after transvenous PM infections in elderly patients, particularly those with severe frailty and PM dependency.

A case of transient ventricular pre-excitation associated with takotsubo cardiomyopathy.

A 75-year-old woman, who had never exhibited a delta wave before, was diagnosed with sigmoid colon cancer and underwent surgical operation. Takotsubo cardiomyopathy (TC) occurred shortly after the operation. About 2 weeks following the onset of TC, a 12­lead electrocardiogram revealed a delta wave that was present for 50 days, and the patient was diagnosed with transient ventricular pre-excitation. The delta wave disappeared prior to patient's discharge and was never observed thereafter. This transient appearance of a delta wave may be related to a pathological modulation of the autonomic nervous system during the acute phase of TC.

Simultaneous infection of abandoned leads and newly implanted leadless cardiac pacemaker: Why did this occur?

An 80-year-old man with a history of dilated hypertrophic cardiomyopathy received a dual-chamber pacemaker for sick sinus syndrome and atrioventricular block in February 2010. On May 30, 2019, he developed pocket erosion, with streaks of pus exuding from the pocket. The pacemaker generator was removed, although both capping leads were left buried under the skin, and a leadless pacemaker was implanted into the right ventricular (RV) apex the next day. Blood and pus cultures on July 15, 2019 indicated methicillin-resistant Staphylococcus aureus (MRSA). The patient was transferred to our hospital for simultaneous removal of both devices in August 2019. The RV lead and right atrial lead were extracted using a laser sheath and a mechanical sheath. A 23 Fr MICRA® sheath was inserted from the right femoral vein to accommodate an 8.5 Fr Agillis sheath. An Osypka LASSO snare catheter was advanced through the sheath to catch the distal aspect of the MICRA® body. Finally, the MICRA® device was completely removed through the sheath. Culture results for the lead tip and MICRA® were both MRSA positive. This is the first report of late-phase simultaneous infection of abandoned leads and implanted leadless cardiac pacemaker extraction. .

Safe and effective transvenous lead extraction for elderly patients utilizing non-laser and laser tools: a single-center experience in Japan.

Transvenous lead extraction (TLE) for cardiac implantable electric device (CIED) infection is becoming increasingly common, but is believed to be particularly risky in elderly patients. This study aimed to clarify the safety and effectiveness of TLE in the elderly, evaluating the use of both non-laser and laser extraction tools. We retrospectively analyzed the characteristics, device type, indications, procedures, and clinical results in younger (YG; age: 15-79 years; n = 48) and elderly groups (EG; age: ≥ 80 years; n = 27) of patients who underwent percutaneous TLE between April 2014 and December 2019 at our hospital. The average age was 68 and 88 years in the YG and EG, respectively. Indications for TLE were infection in 33 (68.8%) patients and other in 15 (30.6%) patients in the YG, and infection in all 27 (100%) EG patients. Bloodstream infection was detected in 9 and 4 patients in the YG and EG, respectively, with methicillin-resistant Staphylococcus epidermidis being the most common causative pathogen. All TLE procedures were performed under general anesthesia in an operating room with cardiovascular surgeon backup. An excimer laser sheath (76 leads), a laser followed by a mechanical sheath (45 leads), Evolution RL® (17 leads), a mechanical sheath (9 leads), and manual traction (one lead) were employed to extract a total of 148 leads (98 and 50 in the YG and EG, respectively). A mechanical sheath or Evolution RL® was more frequently used in the YG. The respective average implantation durations in the YG and EG were 5.3 and 5.0 years, respectively, which were comparable (p = 0.46). Procedural success rates were identical between the YG and EG (99% vs. 100%, respectively). There was only one procedure-related complication in the entire cohort (cardiac tamponade in a YG patient). Taken together, the success rates of TLE were high in the EG, with no complications, with extraction being the indication for infection in all EG patients. Percutaneous TLE was safe and effective in elderly patients using both non-laser and laser techniques.

Rationale and design of the EMPYREAN study.

AIMS: A sodium glucose cotransporter 2 (SGLT2) inhibitor was recently found to reduce heart failure hospitalization in the EMPA-REG OUTCOME trial. We have hypothesized that autonomic nerve activity may be modulated by SGLT2 inhibition. The current study aims to investigate the impact of empagliflozin on sympathetic and parasympathetic nerve activity in patients with type 2 diabetes mellitus. METHODS AND RESULTS: This ongoing study is a prospective, randomized, open-label, multicentre investigation of 134 patients with type 2 diabetes mellitus. The patients are randomly allocated to receive either empagliflozin or sitagliptin with the treatment goal of the Japan Diabetes Society guidelines. Ambulatory electrocardiographic monitoring is performed at the baseline and at 12 and 24 weeks of treatment. Analyses of heart rate variability are conducted using the MemCalc method, which is a combination of the maximum entropy method for spectral analysis and the non-linear least squares method for square analysis. The primary endpoint is the change in the low-frequency (0.04-0.15 Hz)/high-frequency (0.15-0.4 Hz) ratio from baseline to 24 weeks. CONCLUSIONS: This investigation on the effect of EMPagliflozin on cardiac sYmpathetic and parasympathetic neRve activity in JapanEse pAtieNts with type 2 diabetes (EMPYREAN study) offers an important opportunity to understand the impact of SGLT2 inhibition on autonomic nerve activity in patients with type 2 diabetes.

Successful hot balloon ablation for focal atrial tachycardia derived from the left superior pulmonary vein antrum.

A 45-year-old man with paroxysmal atrial fibrillation (PAF) was admitted to our hospital for hot balloon ablation. At admission, atrial tachycardia (AT) was observed. Activation map showed focal atrial tachycardia originating from the posterior wall of the left superior pulmonary vein (LSPV) antrum. We performed hot balloon ablation at the LSPV antrum, terminated AT, and performed pulmonary vein isolation with a hot balloon. The hot balloon was successfully applied for the ablation of the focal atrial tachycardia from the pulmonary vein.

Defibrillation failure with short ICD charge time: Internal short circuit of a Durata lead.

A 17-year-old male with hypertrophic cardiomyopathy underwent placement of a dual-chamber implantable cardioverter defibrillator (ICD) in 2010. In October 2016, he suffered a cardiac arrest. His ICD was interrogated after visiting our hospital. The shock failed, and ventricular fibrillation (VF) terminated spontaneously to sinus rhythm. The Durata lead (SJM, Sylmar, CA, USA) was removed for investigation. The lead had an internal abrasion of a right ventricular conductor cable at the superior vena cava coil. These findings suggest that the ICD shocks that failed to terminate the VF were delivered with low energy due to an internal short circuit of the Durata lead. The very short charge time indicates insufficient energy delivery, which may cause failure of cardioversion and defibrillation. .

Association between reactive hyperemia peripheral arterial tonometry index and atrial fibrillation recurrence after catheter ablation.

BACKGROUND: Vascular endothelial function has recently been recognized as an independent predictor of cardiovascular events. However, studies investigating its association with atrial fibrillation (AF) are lacking. This study aimed to examine association with AF recurrence and vascular endothelial function as assessed using natural logarithmic transformation of reactive hyperemia peripheral arterial tonometry index (LnRHI). METHODS: Ninety-nine consecutive AF patients who underwent catheter ablation (CA) at Shinshu University Hospital between September 2015 and April 2017 were enrolled. LnRHI was measured 48 to 72 h before CA using the EndoPAT system. The primary outcome was AF recurrence beyond 3 months post-ablation. RESULTS: A total of 30 (30.3%) patients experienced AF recurrence after CA over a median follow-up period of 210 days (range: 93-764 days). Female sex and low LnRHI were significantly associated with AF recurrence. In multivariate analysis, LnRHI was an independent predictor of AF recurrence (hazard ratio: 0.087, 95% confidence interval 0.015-0.51, p = 0.007). In comparison in Kaplan-Meier analysis of high LnRHI (LnRHI ≥0.52, n = 52) and low LnRHI (LnRHI ≪0.52, n = 47) groups, AF recurrence rate was significantly higher in the low LnRHI group (log-rank test, p = 0.043). A negative correlation was observed between LnRHI and AF duration, whereby LnRHI was significantly decreased when the duration of AF events exceeded 1 year. CONCLUSION: Decreased LnRHI was associated with AF recurrence after CA and prolonged AF duration.

Wire perforation causing cardiopulmonary arrest during radiofrequency hot balloon ablation for pulmonary vein isolation.

A 73-year-old woman underwent radiofrequency hot balloon ablation (RHBA) for paroxysmal atrial fibrillation. After delivery into the left inferior pulmonary vein (LIPV), the guidewire perforated the venous wall. We injected contrast medium while the inflated balloon occluded the PV. Subsequently, bronchial-pulmonary venous fistula (BPVF) occurred and the severe hypoxia caused pulseless electrical activity (PEA). Cardiopulmonary resuscitation and intubation quickly recovered spontaneous circulation. She was initially treated by a multidisciplinary team in the intensive care unit and subsequently discharged without sequelae. Although relatively rare, there are some reports of wire perforation during RHBA and cryoballoon ablation. Some cases resolved after discontinuing anticoagulant therapy, while others required invasive procedures. This is the first case in which hypoxia, shock, and PEA were caused by wire perforation. As such complications can occur in all balloon ablation procedures, operators need to take care when using the guidewire and guide catheter. Anticoagulant therapy should be discontinued following PV perforation, if possible. Hemostasis with ventilator management is desirable. If hemostasis cannot be achieved, lung resection must be considered. Although wire perforation causing BPVF is rare, establishment of preventive measures and treatment protocols is needed. .

Prognostic significance of high-sensitivity cardiac troponin in patients with heart failure with preserved ejection fraction.

The aim of this study was to investigate the prognostic significance of high-sensitivity troponin T (hs-TnT) in patients with heart failure (HF) with preserved ejection fraction (HFpEF). We enrolled consecutive patients admitted to Shinshu University Hospital for HF treatment between July 2014 and March 2017 and stratified them into HF with reduced ejection fraction and HFpEF groups (left ventricular ejection fraction, < 50% and ≥ 50%, respectively). Hs-TnT was evaluated at discharge, and patients were prospectively monitored for all-cause mortality, non-fatal myocardial infarction, stroke, and HF hospitalization. In 155 enrolled patients (median age 76 years), during a median follow-up of 449 days, 60 experienced an adverse event. Hs-TnT was significantly higher in patients with adverse events than in those without in HFpEF (p = 0.003). Hs-TnT did not significantly correlate with age, sex, hemoglobin, albumin, eGFR, or BNP. In Kaplan-Meier analysis, high hs-TnT predicted a poor prognosis in HFpEF (p = 0.003). In multivariate Cox regression analysis, hs-TnT levels independently predicted adverse events in HFpEF (p = 0.003) after adjusting for age and eGFR [HR, 1.015 (95% CI, 1.005-1.025), p = 0.004], and age and BNP [HR 1.016 (95% CI 1.005-1.027), p = 0.005]. Elevated hs-TnT at discharge predicted adverse events in HFpEF.

Successful inferior vena cava filter removal using pacemaker lead extraction methods.

Inferior vena cava (IVC) filters are often used to treat deep vein thrombosis. IVC filters may become difficult to extract because of adhesion around the device, and those permanently left inside the patient may cause injurious complications. We describe a novel IVC filter extraction technique using pacemaker lead extraction tools. A 26-year-old woman, diagnosed with deep vein thrombosis by computed tomography, received an IVC filter (Gunther Tulip, Cook Medical, Bloomington, IN, USA) implantation for prevention of pulmonary thromboembolism. Eleven weeks later, extraction of the IVC filter by a manual method and snaring technique was unsuccessful because of adhesion to the blood vessel wall. The patient was referred to our hospital for filter removal using pacemaker lead extraction tools. Extraction was performed in an operation room under general anesthesia in the presence of a cardiovascular surgeon, to manage inadvertent perforation. Part of the adhered tissue around the four limbs of the filter was dissected using a 12 Fr laser sheath; protruding anchors were carefully dissected with a telescoping mechanical sheath using a counter-traction technique. Her postoperative course was uneventful, and she was discharged without complications. A sophisticated removal procedure with pacemaker lead extraction tools can be used to remove problematic IVC filters. .

Single-center experience with percutaneous lead extraction of cardiac implantable electric devices.

BACKGROUND: The estimated incidence of infected cardiac implantable electric devices (CIED) has recently increased to 1-2% in Japan. Extraction of long-term implanted devices is generally difficult. There are few reports about lead extraction in Japan. We describe our experience with and outcomes of lead extraction using excimer lasers, mechanical sheaths, and manual extraction. METHODS: We retrospectively analyzed the characteristics, types of devices, and indications for extraction in 29 patients with 67 leads who required CIED lead extraction at Shinshu University Hospital between April 2014 and October 2016. Mean patient age was 71 years and 25 patients were male. The indications for device extraction were infections (n=25) and non-functioning leads (n=4). RESULTS: A total of 67 leads (active fixation lead, n=28; passive fixation lead, n=39) had been implanted for a median duration of 6.3±5.6 years. Extractions were performed using an excimer laser sheath (n=26), laser with mechanical sheath (n=7), only mechanical sheath (Cook Vascular Inc., Leechburg, PA, USA) (n=1), and manually (n=1). The procedure was successful in all patients. There were no major or minor complications during extraction. There was no recurrence of infection after infected device extraction. Two patients were implanted with subcutaneous implantable defibrillators after extraction of the implantable cardioverter defibrillator (ICD). CONCLUSIONS: CIED lead extraction, especially of those that are adherent to the subclavian vein, can be successfully performed in Japanese subjects using an excimer laser and mechanical sheath, without complications.

Geriatric Nutritional Risk Index Predicts Cardiovascular Events in Patients at Risk for Heart Failure.

BACKGROUND: The geriatric nutritional risk index (GNRI) is a simple and objective nutritional assessment tool for elderly patients. Lower GNRI values are associated with a worse prognosis in patients with heart failure (HF). However, few data are available regarding the prognostic effect of the GNRI value for risk stratification in patients at risk for HF.Methods and Results:We retrospectively investigated 1,823 consecutive patients at risk for HF (Stage A/B) enrolled in the IMPACT-ABI Study. GNRI on admission was calculated as follows: 14.89×serum albumin (g/dL)+41.7×body mass index/22. Patients were divided into 2 groups according to the median GNRI value (107.1). The study endpoint was a composite of cardiovascular (CV) events, including CV death and hospitalization for worsening HF. Over a 4.7-year median follow-up, CV events occurred in 130 patients. In the Kaplan-Meier analysis, patients with low GNRI (<107.1, n=904) showed worse prognoses than those with high GNRI (≥107.1, n=919) (20.2% vs. 12.4%, P<0.001). In the multivariable Cox proportional hazards analysis, low GNRI was significantly associated with the incidence of CV events (hazard ratio: 1.48, 95% confidence interval: 1.02-2.14; P=0.040). CONCLUSIONS: The simple and practical assessment of GNRI may be useful for predicting CV events in patients with Stage A/B HF.

Predictive Value of Underweight Status for Patients With Peripheral Artery Disease With Claudication.

We evaluated whether underweight status is associated with poor prognosis in patients with peripheral artery disease (PAD) with claudication, excluding critical limb ischemia. We identified 441 claudicants hospitalized for cardiovascular disease between 2005 and 2012. Patients were divided into 4 groups according to body mass index (BMI): an underweight group (BMI < 18.5 kg/m2; n = 48), a normal group (BMI = 18.5-25.0 kg/m2; n = 286), an overweight group (BMI = 25.0-30.0 kg/m2; n = 92), and an obese group (BMI ≥ 30.0 kg/m2; n = 15). The mean follow-up period was 3.5 ± 1.9 years. The underweight group had significantly lower levels of hemoglobin, albumin, estimated glomerular filtration rate, triglycerides, and hemoglobin A1c; higher levels of C-reactive protein and B-type natriuretic peptide; and a higher prevalence of hemodialysis. The incidence of all-cause death and cardiovascular death was significantly higher in the underweight group (underweight vs normal, 77.1% vs 33.0%; P < .001 and 43.3% vs 14.4%; P < .001, respectively). In a multivariate Cox analysis, underweight status was an independent predictor of all-cause death (hazard ratio, 2.53; 95% confidence interval, 1.58-4.18; P < .001). Therefore, promoting weight gain, as well as managing cardiovascular disease, may be important for underweight patients with PAD.

Ankle-brachial Index for the Prognosis of Cardiovascular Disease in Patients with Mild Renal Insufficiency.

Objective A low ankle-brachial index (ABI) is a known predictor for future cardiovascular events and mortality in patients with chronic kidney disease (CKD). While most prior studies have defined CKD as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, recent reports have suggested that the cardiovascular risk may be increased even in early stages of renal insufficiency. We hypothesized that a low ABI may predict future cardiovascular morbidity and mortality in patients with mild impairment of the renal function. Methods The IMPACT-ABI study was a retrospective, single-center, cohort study that enrolled and obtained ABI measurements for 3,131 patients hospitalized for cardiovascular disease between January 2005 and December 2012. From this cohort, we identified 1,500 patients with mild renal insufficiency (eGFR =60-89 mL/min/1.73 m2), and stratified them into 2 groups: ABI ≤0.9 (low ABI group; 9.2%) and ABI >0.9 (90.8%). The primary outcome measured was the cumulative incidence of major adverse cardiovascular events (MACE; cardiovascular death, myocardial infarction, and stroke). Results Over a mean follow-up of 5.0 years, 101 MACE occurred. The incidence of MACE was significantly higher in patients with low ABI than in those with ABI >0.9 (30.2% vs. 14.4%, log rank p<0.001). A low ABI was associated with MACE in a univariate Cox proportional hazard analysis. A low ABI remained an independent predictor of MACE in a multivariate analysis adjusted for cardiovascular risk factors (hazard ratio (HR): 2.27; 95% confidence interval (CI): 1.33-3.86; p=0.002). Conclusion Low ABI was an independent predictor for MACE in patients with mild renal insufficiency.

Impressive predictive value of ankle-brachial index for very long-term outcomes in patients with cardiovascular disease: IMPACT-ABI study.

BACKGROUND: The ankle-brachial index (ABI) is a marker of generalized atherosclerosis and is predictive of future cardiovascular events. However, few studies have assessed its relation to long-term future cardiovascular events, especially in patients with borderline ABI. We therefore evaluated the relationship between long-term future cardiovascular events and ABI. METHODS: In the IMPACT-ABI study, a single-center, retrospective cohort study, we enrolled 3131 consecutive patients (67 ± 13 years; 82% male) hospitalized for cardiovascular disease and measured ABI between January 2005 and December 2012. After excluding patients with an ABI > 1.4, the remaining 3056 patients were categorized as having low ABI (≤ 0.9), borderline ABI (0.91-0.99), or normal ABI (1.00-1.40). The primary endpoint was MACE (cardiovascular death, myocardial infarction [MI] and stroke). The secondary endpoints were cardiovascular death, MI, stroke, admission due to heart failure, and major bleeding. RESULTS: During a 4.8-year mean follow-up period, the incidences of MACE (low vs. borderline vs. normal: 32.9% vs. 25.0% vs. 14.6%, P<0.0001) and cardiovascular death (26.2% vs. 18.7% vs. 8.9%, P<0.0001) differed significantly across ABIs. The incidences of stroke (9.1% vs. 8.6% vs. 4.8%, P<0.0001) and heart failure (25.7% vs. 20.8% vs. 8.9%, P<0.0001) were significantly higher in the low and borderline ABI groups than in the normal ABI group. But the incidences of MI and major bleeding were similar in the borderline and normal ABI groups. The hazard ratios for MACE adjusted for traditional atherosclerosis risk factors were significantly higher in patients with low and borderline ABI than those with normal ABI (HR, 1.93; 95%CI: 1.44-2.59, P < 0.0001, HR, 1.54; 95% CI: 1.03-2.29, P = 0.035). CONCLUSIONS: The incidence of long-term adverse events was markedly higher among patients with low or borderline ABI than among those with normal ABI. This suggests that more attention should be paid to patients with borderline ABIs, especially with regard to cardiovascular death, stroke, and heart failure.