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Background:

The Västerbotten County in Northern Sweden, and particularly Norsjö municipality, has historically had a high burden of cardiovascular disease, and abdominal aortic aneurysm (AAA).

Aims:

To investigate aspects of aneurysm epidemiology in a population with historically high cardiovascular disease and AAA incidence; specifically:(I)to study the AAA prevalence and associated risk factors in a high-risk population;(II)to study popliteal artery diameter and prevalence of popliteal artery aneurysm (PAA) in a high-risk population;(III) to study risk factors associated with the development of AAA and thoracic aortic aneurysm (TAA);(IV)to study dietary factors and risk for development of AAA and TAA.

Methods & Results:

Population-based screening in Norsjö (ages 65–75) showed a significant decline in AAA prevalence among men (16.9% in 1999 → 5.7% in 2010) and a nonsignificant decline in women (3.5% → 1.1%). Compared to 1999, lipid profiles, BMI, and blood pressure control improved, while smoking remained unchanged at low levels. PAA prevalence ≥12 mm was 3.8% in men and 0% in women; most were small and benign with slow growth rates. In a population-based case-control study, using the prospective VIP/MONICA cohort 1985–2010, smoking, hypertension, hyperlipidemia, and coronary artery disease were significantly associated with later AAA development, while only hypertension was associated with TAA development. In the same case-control cohorts, a weak inverse association between AAA and adherence to a Mediterranean diet or high fruit/vegetable intake was observed.

Conclusion:

The sharp decline in AAA prevalence in Norsjö was mainly attributed to improved cardiovascular risk factors, including diet, rather than smoking habits (as suggested in the literature). AAA and TAA show distinct risk factor profiles, indicating partly different etiologies. PAA is rare, and small screening-detected PAAs appear largely benign.

Objective: Previous studies suggest partly different risk factor profiles of thoracic aortic aneurysms (TAAs) and abdominal aortic aneurysms (AAAs), but prospective data are scarce. The purpose of this prospective population-based case-control study was to investigate differences in risk factor profile between TAAs and AAAs.

Methods: Participants in two prospective population-based studies, the Västerbotten Intervention Project (VIP) and the Monitoring of Trends and Determinants in Cardiovascular Disease (MONICA) study, between 1986 and 2010, underwent cardiovascular risk assessments, including blood samples, oral glucose tolerance test, blood pressure readings, and a self-reported health questionnaire. All individuals who were later diagnosed with TAAs or AAAs were identified. Age, sex, and time-matched controls were selected from the same cohorts, aiming at four controls/case. Adjusted odds ratios (aORs) for potential risk factors for later diagnosis of TAAs and AAAs, respectively, were estimated by multivariate conditional logistic regression analyses.

Results: From a total of 96,196 individuals with prospectively collected data in the VIP/MONICA cohort, a total of 236 individuals with AAAs (181 men and 55 women) and 935 matched controls, and 168 individuals with TAAs (115 men and 53 women) and 662 controls were included. The average age at baseline examination was 57.0 ± 5.7 years for AAA cases and controls, and 52.1 ± 8.8 years for TAA cases and controls. Mean time between baseline examination and diagnosis of AAAs/TAAs was 12.1 and 11.7 years, respectively. There was a clear difference in risk factor profile between AAAs and TAAs. Smoking, hypertension, and coronary artery disease were significantly associated with later diagnosis of AAAs, with highest aORs for a history of smoking (aOR, 10.3; 95% confidence interval [CI], 6.3-16.8). For TAAs, hypertension was the only positive risk factor (aOR, 1.7; 95% CI, 1.1-2.7), whereas smoking was not associated. Diabetes was not associated with either AAAs or TAAs; neither was self-reported physical activity.

Conclusions: In this prospective, population-based, case-control study, risk factor profile differed between AAAs and TAAs. This suggests a partially different etiology for TAAs and AAAs.

Objective: The aim of this study was to determine how many pre-operative ischaemic events occurring within a specific timeframe before carotid endarterectomy (CEA) are needed to increase the peri-operative 30 day risk of stroke or death.

Methods: This was a secondary exploratory analysis based on pooled data from three observational studies sourced from a single centre. Patients with recently symptomatic conventional ≥ 50% carotid stenosis were included. The principal analysis was limited to patients presenting with stroke or transient ischaemic attack (TIA). The primary outcome was 30 day risk of peri-operative stroke or death. Whether one, two, three, or four or more ipsilateral pre-operative ischaemic events within three, seven, 14, or 30 days before CEA were associated with the primary outcome was assessed.

Results: The study included 382 patients who underwent CEA with symptomatic conventional ≥ 50% carotid stenosis with stroke or TIA as the presenting event. Mean patient age ± standard deviation was 72 ± 7 years, 117 (30.6%) were female, and 5% were treated with dual antiplatelet therapy. The primary outcome occurred in 21 patients (5.5%). Two or more events within 7 days before CEA was the most discriminative definition of repeated events, with a 14.3% (8/56) risk of the primary outcome. Those who fell outside this definition of two or more events within seven days before CEA had a 4.0% (13/326; p = .006) risk of experiencing the primary outcome (adjusted odds ratio 4.1, 95% confidence interval 1.6 – 10.5). Several alternative definitions were assessed, but patients with two or more events within seven days before CEA and negative for these alternatives still had a > 10% risk of the primary outcome.

Conclusion: Two or more ipsilateral ischaemic events within seven days before CEA is associated with an increased risk of peri-operative stroke or death in cases with symptomatic conventional ≥ 50% carotid stenosis and TIA or stroke as the presenting event. Studies assessing whether delayed or immediate CEA is preferable for this patient group are warranted.

Objective: Aortic prosthesis infection is a devastating complication of aortic surgery. In situ reconstruction with the neo-aorto-iliac system (NAIS) bypass technique has become increasingly used and is recommended in recent treatment guidelines. The main aim was to evaluate NAIS procedural outcomes when undertaken after previous open or endovascular aortic repair in Sweden.

Methods: In this retrospective study, The National Quality Registry for Vascular Surgery (Swedvasc) was used to identify Swedish centres that offered the NAIS bypass procedure for aortic prosthesis infection between 2008 and 2018. Variables of special interest were procedural details, short and long term survival, renal and other complications, and the durtion of antimicrobial treatment.

Results: Forty patients (36 males, four females [mean age 69 years], 32 open repairs, seven endovascular aortic repairs [EVAR] and one fenestrated EVAR; 21 presented with aorto-enteric fistula) operated on with NAIS bypass were reviewed. The median time from the primary aortic intervention to the NAIS bypass procedure was 32 months (range 0 – 252 months). Mean ± standard deviation operating time was 645 ± 160 minutes, mean blood loss was 6 277 ± 6 525 mL, mean length of intensive care unit stay was 5.3 ± 3.7 days, and mean length of overall hospital stay was 21.2 ± 11.4 days. Thirty-five patients (88%) had a positive microbial culture; the most commonly isolated pathogen was Candida spp. The majority of patients survived for 30 days (n = 35 [88%]), and 33 (83%) and 32 (80%) patients survived for 90 days and one year, respectively. The number of surviving patients free from antimicrobial treatment at 90 days, six months, and one year was 19 (58%), 29 (88%), and 30 (94%). After a mean long term follow up of 69.9 ± 44.7 months, 20 patients were still alive.

Conclusion: The NAIS bypass procedure offered reasonable survival and functional outcomes, and was associated with a high cure rate, defined as freedom from any antimicrobial treatment.

OBJECTIVE: A significant reduction in the incidence of cardiovascular disease, including abdominal aortic aneurysm (AAA), has been observed in the past decades. In this study, a small but geographically well defined and carefully characterized population, previously screened for AAA and risk factors, was re-examined 11 years later. The aim was to study the reduction of AAA prevalence and associated factors.

METHODS: All men and women aged 65 to 75 years living in the Norsjö municipality in northern Sweden in January 2010 were invited to an ultrasound examination of the abdominal aorta, registration of body parameters and cardiovascular risk factors, and blood sampling. An AAA was defined as an infrarenal aortic diameter ≥30 mm. Results were compared with a corresponding investigation conducted in 1999 in the same region.

RESULTS: A total of 602 subjects were invited, of whom 540 (90%) accepted. In 2010, the AAA prevalence was 5.7% (95% confidence interval [CI], 2.8%-8.5%) among men compared with 16.9% (95% CI, 12.3%-21.6%) in 1999 (P < .001). The corresponding figure for women was 1.1% (95% CI, 0.0%-2.4%) vs 3.5% (95% CI, 1.2%-5.8%; P = .080). A low prevalence of smoking was observed in 2010 as well as in 1999, with only 13% and 10% current smokers, respectively (P = .16). Treatment for hypertension was significantly more common in 2010 (58% vs 44%; P < .001). Statins increased in the population (34% in 2010 vs 3% in 1999; P < .001), and the lipid profile in women had improved significantly between 1999 and 2010.

CONCLUSIONS: A highly significant reduction in AAA prevalence was observed during 11 years in Norsjö. Treatment for hypertension and with statins was more frequent, whereas smoking habits remained low. This indicates that smoking is not the only driver behind AAA occurrence and that lifestyle changes and treatment of cardiovascular risk factors may play an equally important role in the observed recent decline in AAA prevalence.

We developed a technique for direct start of peritoneal dialysis. Using a coiled or straight Tenckhoff catheter often results in obstruction of flow. A self-locating Wolfram catheter is on the market. It is not clarified if this results in a benefit.The primary aim of this study was to perform a randomized investigation to clarify if the use of a self-locating peritoneal dialysis (PD) catheter would result in different flow problems than a straight Tenckhoff catheter.A total of 61 insertions were made who were randomized and received either a straight Tenckhoff (n = 32) or a self-locating Wolfram catheter (n = 29). A previously described operation technique allowed immediate postoperative start of dialysis. Seven straight Tenckhoff catheters had to be changed into self-locating catheters, and none vice versa, due to flow problems (P = 0.011). An early leakage resulted in temporarily postponed PD in 4 patients. This study showed that using the present operation technique the self-locating PD-catheter causes fewer obstruction episodes than a straight Tenckhoff catheter. This facilitates immediate postoperative start of PD.