Supra-normal values of resting left ventricular systolic function are associated with decreased survival: to good to be normal?

Background

Hyper-contractile phenotype of the left ventricle (LV) is generally considered prognostically benign, but recent data challenge this intuitive assumption.

Aim

To assess the effects of resting LV function on survival.

Methods

In a prospective, observational, multicenter study, we recruited 5,122 patients (age 65±11.1 years, 2974 males, 58%) with chronic coronary syndromes referred for resting transthoracic echocardiography with technically successful volumetric echocardiography in 14 accredited laboratories. All recruiting centers had a structured follow-up program with >90% follow-up rate. In each patient, we quantitatively assessed (by Simpson's biplane, apical single-plane or parasternal linear method) LV end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF). As a load-independent index of LV contractility, LV force was estimated as systolic blood pressure by cuff sphygmomanometer/ESV. All-cause death was the only considered outcome end-point.

Results

EF was 59±11% (normal reference sextile = 58.0–59.9%). Force was 4.51±2.11 mmHg/ml (normal reference sextile = 3.50–4.27 mmHg/ml). The correlation between EF and force was linear (r=0.585, p<0.001). After a median follow-up of 862 days, there were 265 all-cause deaths. Considering EF values, mortality was lowest in the highest sextile (>67%) and significantly higher in the lowest sextile (EF <52%): see figure, left panel. A U-shaped curve was found with force, with mortality values being lowest in the middle sextile and significantly higher in the lowest sextile (<2.59 mmHg/ml) and in the highest sextile (>6.36 mmHg/ml): see figure, right panel. At multivariable analysis, after adjustment for age, diabetes, EF, and prior myocardial infarction, both the highest sextile of force (HR 1.84, 95%, confidence intervals 1.12–3.03 p=0.015), and the lowest sextile of force (HR 1.77, 95%, confidence intervals 1.08–2.90 p=0.024) were associated with decreased survival.

Conclusion

Sub-normal values of resting ejection fraction and super- and sub-normal values of the force are associated with worse survival in patients with chronic coronary syndromes. This U-shaped curve of mortality is detectable only with the force, a load independent index of LV contractility: too much of a good thing such as LV contractility can be dangerous on the long-run.

Funding Acknowledgement

Type of funding sources: None.

Prognostic value of rest B-lines with the simplified 4-site scan for predicting survival: incremental value over transthoracic echocardiography

Background

Lung ultrasound (LUS) detects pulmonary congestion as B-lines at rest.

Methods

After preliminary exclusion of 154 patients lost to follow-up, we analyzed transthoracic echocardiography (TTE) plus LUS (4-site simplified scan) data in 5165 subjects (age 64±11 years) referred to 19 certified centers of 9 countries for known or suspected coronary artery disease (n=3891, 75%), dyspnea (n=591, 12%), or screening in asymptomatic patients with risk factors (n=667, 13%). We analyzed the anterior and lateral hemi-thoraces, scanning from mid-axillary to mid-clavicular lines on the third intercostal space. B-lines score ranged from 0 (normal) to 40 (severely abnormal). By selection, follow-up information was available in all. All-cause death was the predetermined end-point.

Results

Feasibility of B-lines was 100% in all subjects. B-lines (median) were 0.1 [0–1]. Rest B-lines (≥2) were present in 863 patients (16.7%). Ejection fraction was 61±10%. After a median follow-up of 690 (Interquartile range 420–1065) days, 96 all-cause deaths occurred. Two-year mortality was 3.6% in patients with and 1.5% in patients without B-lines (p<0.001) and increased progressively with the increasing number of B-lines, from 2.4% in mild (2–4, n=630), 5.0% in moderate (5–9, n=160) and 8.2% in patients with severe (≥10, n=73) B-lines (see figure). At multivariable analysis, rest B lines (HR 1.812, 95% CI: 1.165–2.916, p=0.008) and ejection fraction (HR 0.987, 95% CI: 0.976–0.998, p=0.020) were independent predictors of all-cause death, in addition to age (HR 1.045, 95% CI: 1.023–01.067, p<0.001) and diabetes (HR 1.643, 95% CI: 1.079–2.503, p=0.021).

Conclusion

In all-comers referred for TTE, resting B-lines assessed by focused LUS with the simplified 4-site scan are detected in 1 out of 4 patients with symptos or coronary risk factors and are associated with worse survival. The severity of pulmonary congestion predicts the severity of outcomes. The prognostic value of resting B-lines is independent and additive over standard clinical and TTE predictors such as diabetes and ejection fraction. Focused LUS for pulmonary congestion can easily be incorporated in standard TTE examination.

Funding Acknowledgement

Type of funding sources: None.

Pulmonary Congestion During Exercise Stress Echocardiography in Ischemic and Heart Failure Patients

BACKGROUND

Lung ultrasound detects pulmonary congestion as B-lines at rest, and more frequently, during exercise stress echocardiography (ESE).

METHODS

We performed ESE plus lung ultrasound (4-site simplified scan) in 4392 subjects referred for semi-supine bike ESE in 24 certified centers in 9 countries. B-line score ranged from 0 (normal) to 40 (severely abnormal). Five different populations were evaluated: control subjects (n=103); chronic coronary syndromes (n=3701); heart failure with reduced ejection fraction (n=395); heart failure with preserved ejection fraction (n=70); ischemic mitral regurgitation ≥ moderate at rest (n=123). In a subset of 2478 patients, follow-up information was available.

RESULTS

During ESE, B-lines increased in all study groups except controls. Age, hypertension, abnormal ejection fraction, peak wall motion score index, and abnormal heart rate reserve were associated with B-lines in multivariable regression analysis. Stress B lines (hazard ratio, 2.179 [95% CI, 1.015-4.680]; P=0.046) and ejection fraction <50% (hazard ratio, 2.942 [95% CI, 1.268-6.822]; P=0.012) were independent predictors of all-cause death (n=29 after a median follow-up of 29 months).

CONCLUSIONS

B-lines identify the pulmonary congestion phenotype at rest, and more frequently, during ESE in ischemic and heart failure patients. Stress B-lines may help to refine risk stratification in these patients.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03049995.

Pulmonary congestion during exercise stress echocardiography in ischaemic, heart failure and valvular patients

Background

Lung ultrasound (LUS) detects pulmonary congestion as B-lines at rest and exercise stress echocardiography (ESE).

Aim

To assess the prevalence of B-lines during ESE in different cardiovascular diseases.

Methods

We performed ESE plus LUS (4-site simplified scan) in 4419 subjects referred for semi-supine bike ESE in 28 certified centers. B-lines score ranged from 0 (normal) to 40 (severely abnormal). Stress B-lines abnormal result was ≥2 units. Six different populations were evaluated: healthy controls (n=103); chronic coronary syndromes (CCS, n=3701); heart failure with reduced ejection fraction (HFrEF, n=395); heart failure with preserved ejection fraction (HFpEF, n=70); valvular heart disease (VHD) for ischemic mitral regurgitation ≥moderate at rest (n=123); repaired tetralogy of Fallot (ToF, n=27).

Results

Feasibility of B-lines was 100% at rest and peak ESE in all subjects. Imaging and analysis time were &lt;1 minute. B-lines (median) were not detectable in healthy subjects (rest=0.1 [0–1] vs 0.1 [0–1], p=ns) and TOF (rest=0.2 [0–2] vs 0.3 [0–4], p=ns), but were present in all other groups: see figure. During ESE, B-lines increased in CCS (rest=0.5 [0–24] vs ESE=1.3 [0–28], p&lt;0.001); HFrEF (rest=1.4 [0–35] vs ESE=2.9 [0–40], p&lt;0.001); HFpEF (rest=0.3 [0–2] vs ESE=3.4 [0–12], p&lt;0.001), VHD (rest=1.7 [0–12] vs ESE=4.3 [0–23], p&lt;0.001). Stress B-lines were correlated with stress-rest change in wall motion score index in CCS (r=0.325, p&lt;0.001), contractile reserve in HFrEF (r=−0.266, p&lt;0.001) and in VHD (r=−.0300, p=0.001), left atrial volume stress-rest change in HFpEF (r=0.287, p=0.043).

Conclusion

B-lines identify the pulmonary congestion phenotype at rest and more frequently during ESE in patients with different coronary, myocardial or valvular heart disease, all sharing the final common pathway of acute backward left heart failure through different disease-specific mechanisms. B-lines are absent in healthy subjects and in conditions inducing a mostly right-sided overload such as repaired ToF.

Funding Acknowledgement

Type of funding sources: None. Figure 1. B-lines at rest and during stress. Percentage (%) of rest (empty bar) and stress (full bar) B-lines abnormality (≥2 units) in six different study groups.

Hemodynamic Heterogeneity of Reduced Cardiac Reserve Unmasked by Volumetric Exercise Echocardiography

Background: Two-dimensional volumetric exercise stress echocardiography (ESE) provides an integrated view of left ventricular (LV) preload reserve through end-diastolic volume (EDV) and LV contractile reserve (LVCR) through end-systolic volume (ESV) changes. Purpose: To assess the dependence of cardiac reserve upon LVCR, EDV, and heart rate (HR) during ESE. Methods: We prospectively performed semi-supine bicycle or treadmill ESE in 1344 patients (age 59.8 ± 11.4 years; ejection fraction = 63 ± 8%) referred for known or suspected coronary artery disease. All patients had negative ESE by wall motion criteria. EDV and ESV were measured by biplane Simpson rule with 2-dimensional echocardiography. Cardiac index reserve was identified by peak-rest value. LVCR was the stress-rest ratio of force (systolic blood pressure by cuff sphygmomanometer/ESV, abnormal values ≤2.0). Preload reserve was defined by an increase in EDV. Cardiac index was calculated as stroke volume index * HR (by EKG). HR reserve (stress/rest ratio) <1.85 identified chronotropic incompetence. Results: Of the 1344 patients, 448 were in the lowest tertile of cardiac index reserve with stress. Of them, 303 (67.6%) achieved HR reserve <1.85; 252 (56.3%) had an abnormal LVCR and 341 (76.1%) a reduction of preload reserve, with 446 patients (99.6%) showing ≥1 abnormality. At binary logistic regression analysis, reduced preload reserve (odds ratio [OR]: 5.610; 95% confidence intervals [CI]: 4.025 to 7.821), chronotropic incompetence (OR: 3.923, 95% CI: 2.915 to 5.279), and abnormal LVCR (OR: 1.579; 95% CI: 1.105 to 2.259) were independently associated with lowest tertile of cardiac index reserve at peak stress. Conclusions: Heart rate assessment and volumetric echocardiography during ESE identify the heterogeneity of hemodynamic phenotypes of impaired chronotropic, preload or LVCR underlying a reduced cardiac reserve.

Feasibility and functional correlates of left atrial volume changes during stress echocardiography in chronic coronary syndromes

An enlarged left atrial volume index (LAVI) at rest mirrors increased LA pressure and/or impairment of LA function. A cardiovascular stress may acutely modify left atrial volume (LAV) within minutes. Aim of this study was to assess the feasibility and functional correlates of LAV-stress echocardiography (SE) Out of 514 subjects referred to 10 quality-controlled labs, LAV-SE was completed in 490 (359 male, age 67 ± 12 years) with suspected or known chronic coronary syndromes (n = 462) or asymptomatic controls (n = 28). The utilized stress was exercise in 177, vasodilator in 167, dobutamine in 146. LAV was measured with the biplane disk summation method. SE was performed with the ABCDE protocol. The intra-observer and inter-observer LAV variability were 5% and 8%, respectively. ∆-LAVI changes (stress-rest) were negatively correlated with resting LAVI (r = - 0.271, p < 0.001) and heart rate reserve (r = -.239, p < 0.001). LAV-dilators were defined as those with stress-rest increase ≥ 6.8 ml/m², a cutoff derived from a calculated reference change value above the biological, analytical and observer variability of LAVI. LAV dilation occurred in 56 patients (11%), more frequently with exercise (16%) and dipyridamole (13%) compared to dobutamine (4%, p < 0.01). At multivariable logistic regression analysis, B-lines ≥ 2 (OR: 2.586, 95% CI = 1.1293-5.169, p = 0.007) and abnormal contractile reserve (OR: 2.207, 95% CI = 1.111-4.386, p = 0.024) were associated with LAV dilation. In conclusion, LAV-SE is feasible with high success rate and low variability in patients with chronic coronary syndromes. LAV dilation is more likely with reduced left ventricular contractile reserve and pulmonary congestion.

Lung Ultrasound and Pulmonary Congestion During Stress Echocardiography

OBJECTIVES

The purpose of this study was to assess the functional and prognostic correlates of B-lines during stress echocardiography (SE).

BACKGROUND

B-profile detected by lung ultrasound (LUS) is a sign of pulmonary congestion during SE.

METHODS

The authors prospectively performed transthoracic echocardiography (TTE) and LUS in 2,145 patients referred for exercise (n = 1,012), vasodilator (n = 1,054), or dobutamine (n = 79) SE in 11 certified centers. B-lines were evaluated in a 4-site simplified scan (each site scored from 0: A-lines to 10: white lung for coalescing B-lines). During stress the following were also analyzed: stress-induced new regional wall motion abnormalities in 2 contiguous segments; reduced left ventricular contractile reserve (peak/rest based on force, ≤2.0 for exercise and dobutamine, ≤1.1 for vasodilators); and abnormal coronary flow velocity reserve ≤2.0, assessed by pulsed-wave Doppler sampling in left anterior descending coronary artery and abnormal heart rate reserve (peak/rest heart rate) ≤1.80 for exercise and dobutamine (≤1.22 for vasodilators). All patients completed follow-up.

RESULTS

According to B-lines at peak stress patients were divided into 4 different groups: group I, absence of stress B-lines (score: 0 to 1; n = 1,389; 64.7%); group II, mild B-lines (score: 2 to 4; n = 428; 20%); group III, moderate B-lines (score: 5 to 9; n = 209; 9.7%) and group IV, severe B-lines (score: ≥10; n = 119; 5.4%). During median follow-up of 15.2 months (interquartile range: 12 to 20 months) there were 38 deaths and 28 nonfatal myocardial infarctions in 64 patients. At multivariable analysis, severe stress B-lines (hazard ratio [HR]: 3.544; 95% confidence interval [CI]: 1.466 to 8.687; p = 0.006), abnormal heart rate reserve (HR: 2.276; 95% CI: 1.215 to 4.262; p = 0.010), abnormal coronary flow velocity reserve (HR: 2.178; 95% CI: 1.059 to 4.479; p = 0.034), and age (HR: 1.031; 95% CI: 1.002 to 1.062; p = 0.037) were independent predictors of death and nonfatal myocardial infarction.

CONCLUSIONS

Severe stress B-lines predict death and nonfatal myocardial infarction. (Stress Echo 2020-The International Stress Echo Study [SE2020]; NCT03049995).

Feasibility and value of two-dimensional volumetric stress echocardiography

BACKGROUND

Stroke volume response during stress is a major determinant of functional status in heart failure and can be measured by two-dimensional (2-D) volumetric stress echocardiography (SE). The present study hypothesis is that SE may identify mechanisms underlying the change in stroke volume by measuring preload reserve through end-diastolic volume (EDV) and left ventricular contractile reserve (LVCR) with systolic blood pressure and end-systolic volume (ESV).

METHODS

We enrolled 4735 patients (age 63.6±11.3 years, 2800 male) referred to SE for known or suspected coronary artery disease (CAD) and/or heart failure (HF) in 21 SE laboratories in 8 countries. In addition to regional wall motion abnormalities (RWMA), force was measured at rest and peak stress as the ratio of systolic blood pressure by cuff sphygmomanometer/ESV by 2D with Simpson's or linear method. Abnormal values of LVCR (peak/rest) based on force were ≤1.10 for dipyridamole (N.=1992 patients) and adenosine (N.=18); ≤2.0 for exercise (N.=2087) or dobutamine (N.=638).

RESULTS

Force-based LVCR was obtained in all 4735 patients. Lack of stroke volume increase during stress was due to either abnormal LVCR and/or blunted preload reserve, and 57% of patients with abnormal LVCR nevertheless showed increase in stroke volume.

CONCLUSIONS

Volumetric SE is highly feasible with all stresses, and more frequently impaired in presence of ischemic RWMA, absence of viability and reduced coronary flow velocity reserve. It identifies an altered stroke volume response due to reduced preload and/or contractile reserve.

Feasibility and value of two-dimensional volumetric stress echocardiography

BACKGROUND

Stroke volume response during stress is a major determinant of functional status in heart failure and can be measured by two-dimensional (2-D) volumetric stress echocardiography (SE). The present study hypothesis is that SE may identify mechanisms underlying the change in stroke volume by measuring preload reserve through end-diastolic volume (EDV) and left ventricular contractile reserve (LVCR) with systolic blood pressure and end-systolic volume (ESV).

METHODS

We enrolled 4,735 patients (age 63.6 ± 11.3 yrs, 2800 male) referred to SE for known or suspected coronary artery disease (CAD) and/or heart failure (HF) in 21 SE laboratories in 8 countries. In addition to regional wall motion abnormalities (RWMA), force was measured at rest and peak stress as the ratio of systolic blood pressure by cuff sphygmomanometer/ESV by 2D with Simpson's or linear method. Abnormal values of LVCR (peak/rest) based on force were ≤1.10 for dipyridamole (n=1,992 patients) and adenosine (n=18); ≤2.0 for exercise (n=2,087) or dobutamine (n=638).

RESULTS

Force-based LVCR was obtained in all 4,735 pts. Lack of stroke volume increase during stress was due to either abnormal LVCR and/or blunted preload reserve, and 57 % of patients with abnormal LVCR nevertheless showed increase in stroke volume.

CONCLUSIONS

Volumetric SE is highly feasible with all stresses, and more frequently impaired in presence of ischemic RWMA, absence of viability and reduced coronary flow velocity reserve. It identifies an altered stroke volume response due to reduced preload and/or contractile reserve.

Reduced pulmonary vascular reserve during stress echocardiography in confirmed pulmonary hypertension and patients at risk of overt pulmonary hypertension

Noninvasive estimation of systolic pulmonary artery pressure (SPAP) during exercise stress echocardiography (ESE) is recommended for pulmonary hemodynamics evaluation but remains flow-dependent. Our aim was to assess the feasibility of pulmonary vascular reserve index (PVRI) estimation during ESE combining SPAP with cardiac output (CO) or exercise-time and compare its value in three group of patients: with invasively confirmed pulmonary hypertension (PH), at risk of PH development (PH risk) mainly with systemic sclerosis and in controls (C) without clinical risk factors for PH, age-matched with PH risk patients. We performed semisupine ESE in 171 subjects: 31 PH, 61 PH at risk and 50 controls as well as in 29 young, healthy normals. Rest and stress assessment included: tricuspid regurgitant flow velocity (TRV), pulmonary acceleration time (ACT), CO (Doppler-estimated). SPAP was calculated from TRV or ACT when TRV was not available. We estimated PVRI based on CO (peak CO/SPAP*0.1) or exercise-time (ESE time/SPAP*0.1). During stress, TRV was measurable in 44% patients ACT in 77%, either one in 95%. PVRI was feasible in 65% subjects with CO and 95% with exercise-time (p < 0.0001). PVRI was lower in PH compared to controls both for CO-based PVRI (group 1 = 1.0 ± 0.95 vs group 3 = 4.28 ± 2.3, p < 0.0001) or time-based PVRI estimation (0.66 ± 0.39 vs 3.95 ± 2.26, p < 0.0001). The proposed criteria for PH detection were for CO-based PVRI ≤ 1.29 and ESE-time based PVRI ≤ 1.0 and for PH risk ≤ 1.9 and ≤ 1.7 respectively. Noninvasive estimation of PVRI can be obtained in near all patients during ESE, without contrast administration, integrating TRV with ACT for SPAP assessment and using exercise time as a proxy of CO. These indices allow for comparison of pulmonary vascular dynamics in patients with varied exercise tolerance and clinical status.

P944 From systolic pulmonary arterial pressure to pulmonary vascular resistance and reserve: a simplified method for exercise stress echocardiography

OnBehalf

On behalf of Stress Echo 2020 study group of the Italian Society of Echocardiography and Cardiovascular Imaging (SIECVI).

Background

The potential of exercise stress echocardiography (ESE) seems to be still underused especialy in the assessment of pulmonary hemodynamics.

Aim

To assess the feasibility and compare pulmonary vascular resistance (PVResistance) and reserve (PVReserve) during ESE in patients at risk of pulmonary hypertension (PH) and controls.

Methods

We performed semi-supine ESE, in 97 subjects (age 49 ± 16 yrs, 63 females): 58 patients (Group 1) at risk for PH (systemic sclerosis and other connective tissue diseases) and 39 healthy controls (Group 2). Rest and stress assessment included: tricuspid regurgitant velocity (TRV), pulmonary acceleration time (ACT), cardiac output (CO), SPAP estimation with Bernouilli equation or from ACT with formula: log10 SPAP= - 0.004 (ACT) + 2.1. We estimated PVResistance from Abbas formula, and PVReserve as ΔCO/ ΔSPAP or (when CO was not available) as minutes of exercise/ΔSPAP. When ΔSPAP was &lt;10 mmHg, it was considered equal to 1.

Results

With TRV or ACT to estimate pressures, and cardiac output or its proxy to estimate flow, PVResistance or PVReserve could be measured in all patients. At peak exercise, PVResistance was higher and PVReserve lower in Group 1 : see Table.

Conclusion

Estimation of PVResistance and/or PVReserve can be obtained in all patients during ESE, integrating TRV with ACT, and using exercise-time as a proxy of CO when the latter is not available. These indices may be useful for a better, noninvasive characterization of the heterogeneity of pulmonary hemodynamics.

Pulmonary hemodynamics ESE data Parameter Group 1, PH (n = 58) Group 2, normals (n = 39) P value TRV rest (cm/s) 243 ± 63 204 ± 31 =0.0147 TRV peak (cm/s) 344 ± 68 204 ± 53 &lt;0.0001 ACT rest (ms) 113 ± 33 128 ± 20 =0.0205 ACT peak (ms) 86 ± 19 94 ± 22 ns SPAP rest (mm Hg) 26 ± 10 21 ± 4 =0.0039 SPAP peak (mm Hg) 45 ± 19 28 ± 13 &lt;0.0001 CO rest (mL/min) 4.9 ± 1.7 5.1 ± 1.7 ns CO peak (mL/min) 7.8 ± 2.8 7.6 ± 2.9 ns Exercise time (min) 7 ± 2 13 ± 3 &lt;0.0001 PVResistance (WU) rest 1.63 ± 0.52 1.54 ± 0.34 ns PVResistance (WU) peak 2.01 ± 0.89 1.27 ± 0.42 =0.0219 PVReserve (ΔCO/ΔSPAP) 1.38 ± 1.13 3.55 ± 2.45 =0.001 PVReserve (Extime/ΔSPAP) 4.69 ± 2.67 10.96 ± 4.39 &lt;0.0001 Legends: WU -Wood Unit, Ex time - exercise time

P1402 The behavior of regional longitudinal strain depends on the coronary reserve in a simultaneous analysis during Dipyridamol Stress Echocardiography Test

Objectives

Compare the behavior of the Apical LS and GLS with the value of the CFR in the LADA and as a secondary objective to compare these responses with a simultaneous visual analysis of the motility during EchoDipi.

Materials and methods

179 patients (p) were included (age 68.7 ± 7 years). Of them, 113p(65%) were men. At the peak of the effect of Dipi(0.84mg/kg in 4m) the CFR was measured in the distal region of the LADA(Normal Value≥2). The subjects were divided into 2 groups(G): G1: p with CFR of the LAD≥2 and G2 p with LADA CFR &lt; 2. ApRLS was defined as the average of the 4 apical segments, in 4, 3 and 2 apical views, considering any increase in the percentage of deformation as normal. The LGS and wall motility of the 17 segments were evaluated; p with LBBB or wall motion abnormalities were excluded.

Results

Of 179 p, 113p(63.12%) were included in G1 and 66p(36.87%) in G2. G1 were older(65.9 ± 10.27 vs 72.2 ± 9.31,p &lt; 0.02), without significant differences in other clinical characteristics. No differences in the values of LGS and the Ap RLS at rest between G1 and G2 (GLS: G1: -19.8 ± 4.8 vs G2: -20.27 ± 2.6 p = NS; Ap RLS G1: -25.41 ± 4.75 vs G2: -26.73 ± 7.6 p = NS). During EchoDipi GLS and Ap RLS increased in the pts of G1 with a significant worsening in the G2 (SLG: G1: -22.98 ± 4.31 vs G2: -17.82 ± 2.70, p &lt; 0.0001; Ap SLR G1: -28.43 ± 5.6 vs. G2: -22.78 ± 7.41, p &lt; 0.0001). We observed that in 96.7% of p G1 the ApRLS increased strain with the stress meanwhile 95.31% of the G2 decrease(p &lt; 0.0001). Negative predictive value (NPV) :95.6%(CI = 87.8-98.5%), positive predictive value (PPV) =96.8%(CI = 89.0-99.1%).Specificity(E): 97%(CI = 89.9-99.2%),Sensibility(S): 95.2%(CI = 86.9-98.4%). Area Under the ROC curve(AUC)=0.92. The behavior of the GLS showed that 82.8% of the pts of the G1 during EchoDipi increased their Strain values in contrast with 78.8% p of the G2 decrease p &lt; 0.01).NPV 78.8%(CI = 67.5-86.9%),PPV:90.8%(CI = 83.9-94.9%),E:83.9% (CI = 72.8-91.0%),S:87.6%(CI = 80.3-92.5%).AUC ROC= 0.84. The analysis of wall motility showed that 96.46%(109p) of G1 had preserved wall motility, 1 p showed contractility abnormalities and decreased ApRLS. Of the G2, 36p showed conserved contractility during the stress.

Conclusions.There was a close correlation between LADA coronary flow reserve and the contractile reserve evaluated by regional longitudinal strain of the 4 apical segments, which was superior to the use of global longitudinal strain. The Apical Strain showed a better correlation with the LADA coronary flow reserve than with the visual analysis of wall motion.

P1792 Coronary flow velocity reserve and prognosis during stress echocardiography

OnBehalf

Stress Echo 2020 study group of the Italian Society of Cardiovascular Imaging

Background

Stress echocardiography (SE) based on regional wall motion abnormalities (RWMA) has established risk stratification capabilities, further enhanced by assessment of coronary flow velocity reserve (CFVR) on mid-distal left anterior descending coronary artery which assesses not only epicardial coronary artery stenosis but also coronary microcirculation.

Aim

To assess the value of CFVR in predicting outcome

Methods

From September 2016 to December 2018, we enrolled 1848 patients (age 63 ± 11 years; 1121 males, 60%) with known or suspected coronary artery disease and/or heart failure evaluated with SE (exercise in 631, dipyridamole in 1184, adenosine in 10, dobutamine in 43) in 9 quality-controlled centers of 6 countries. CFVR was measured from pulsed wave Doppler as peak/rest ratio of peak diastolic flow. All patients were followed-up for a median of 16 months.

Results CFV was 28 ± 10 cm/s at rest and 62 ± 19 cm/s at peak stress (p&lt;.001) with a CFVR of 2.25 ± 0.58. At individual patient analysis, CFVR was abnormal (≤2.0) in 528 (28%) patients: 265 (42%) with exercise, 254 (21%) with vasodilator and 9 (21%) with dobutamine stress. At follow-up, there were 218 events: 22 deaths, 22 non-fatal myocardial infarctions, 62 acute heart failures, and 112 late (&gt; 3 months from SE) myocardial revascularizations. At multivariable analysis, stress-induced RWMA (Hazard Ratio 3.883, 95% Confidence Intervals: 2.379-6.336, p&lt;.0.001) and CFVR (Hazard Ratio 1.590, 95% Confidence Intervals: 1.123-2.275, p&lt;.009) were independent predictors. Kaplan-Meier curves showed progressively worsening event-free survival with progressively lower values of CFVR: see figure

Conclusion In patients referred to SE, CFVR assessing coronary microvascular dysfunction allows a more accurate prediction of outcome than RWMA which only detect epicardial coronary artery stenoses.

Abstract P1792 Figure. CFVR and event-free survival curves

P1401 The prognostic value of the reduction of coronary flow velocity reserve in non-ischemic heart failure patients

OnBehalf

Stress Echo 2020 study group of the Italian Society of Cardiovascular Imaging

Background

Coronary microvascular abnormalities determining a reduction of coronary flow velocity reserve (CFVR) have been described in patients (pts) with non-ischemic heart failure (HF).

Aim

To assess the prognostic value of CFVR in HF.

Methods

In a prospective, observational, multicenter study, we recruited 333 pts with angiographically normal coronary arteries: 105 patients with HF and preserved (&gt;50%) ejection fraction (HFpEF); 71 with HF and mid-range (40-50%) ejection fraction (HFmrEF); 157 with HF and reduced (&lt;40%) ejection fraction (HFrEF). All patients underwent vasodilator SE with dipyridamole (0.84 mg/kg) in 10 accredited laboratories of 5 countries (Argentina, Brazil, Italy, Mexico, Serbia). CFVR was calculated as the stress/rest ratio of diastolic peak flow velocity pulsed wave-Doppler assessment of LAD flow. In all patients we also assessed left ventricular contractile reserve (LVCR) based on force (systolic blood pressure/end-systolic volume) Abnormal cutoff values were ≤2.0 for CFVR and ≤1.1 for LVCR. All pts were followed-up.

Results

After a median follow-up time of 15 months, 78 events occurred: 36 hospital admissions for acute decompensated heart failure, 23 deaths, 16 worsening in NYHA functional class, 2 stroke and 1 late revascularization. Event-free survival was best in patients with preserved CFVR and LVCR and worst in pts with reduced CFVR and impaired LVCR, with intermediate values for patients with either one (CFVR or LVCR) abnormal results: see figure. A preserved CFVR was associated with a better 24-month event-free survival than reduced CFVR in a subset analysis in pts with HFpEF (HR = 16.2, 95% CI, 1.8-145.1, p = 0.001) and in HFrEF (HR = 3.06, 95% CI, 1.6-5.6, p &lt; 0.001). A multivariable analysis in the overall group of HF pts identified a reduced CFVR as the only independent predictor of event-free survival (HR = 3.455,95% CI 1.723-6.929).

Conclusions

A reduction in CFVR identifies a high risk subset in HF patients, outlining a shared role of coronary microvascular abnormalities as a marker and potential therapeutic target of HF, independently of underlying EF.

Abstract P1401 Figure. Event-free survival based on CFVR-LVCR

1675 ABCDE vasodilator stress echocardiography in non-ischemic heart failure

OnBehalf

Stress Echo 2020 study group of the Italian Society of Cardiovascular Imaging

Background

ABCDE-stress echocardiography (SE) may explore different aspects in the heterogeneous entity of known or suspected heart failure (HF).

Aim

To assess ABCDE-vasodilator SE in non-ischemic HF

Methods

In a prospective, observational, multicenter study, we recruited 428 patients with angiographically normal coronary arteries: 148 patients with HF and preserved (&gt;50%) ejection fraction (HFpEF, Group 1); 100 with HF and mid-range (40-50%) ejection fraction (HFmrEF, Group 2); 180 with HF and reduced (&lt;40%) ejection fraction (HFrEF, Group 3). A group of 75 healthy asymptomatic patients (30 male, 40%, age 57 ± 14 years) referred to testing for screening was also selected (Controls). All patients underwent vasodilator SE with dipyridamole (0.84 mg/kg) in 14 accredited laboratories of 5 countries (Argentina, Brasil, Russian Federation, Serbia and Italy). The ABCDE-SE protocol was adopted: A for regional wall motion abnormalities; B for B-lines (positivity criterion: stress ≥ rest for ≥ 2 points in a 4-site simplified scan available in 181 pts and 10 controls); C for left ventricular contractile reserve (LVCR) based on force (systolic blood pressure/end-systolic volume, positivity criterion: peak/ rest ≤1.1); D for pulsed wave Doppler-based assessment of coronary flow velocity reserve (CFVR) in left anterior descending coronary artery (positivity criterion: peak/rest ≤2.0); E for EKG-based assessment of heart rate reserve (positivity criterion: peak/rest ≤1.22).

Results

All positivity criteria, except A, were more prevalent (p&lt;.01) in Group 3 compared to Group 2, in Group 2 compared to Group 1, and Group 1 compared to controls: see figure. In particular, a blunted heart rate reserve was found in 4/75 controls (5%), 27/148 pts of Group 1 (18%), 28/100 of Group 2 (28%) and 98/180 of Group 3 (54%).

Conclusions

ABCDE-vasodilator SE can help to identify the profound pathophysiological heterogeneity underlying a similar clinical presentation in patients with known or suspected HF with angiographically normal coronary arteries. These patients rarely show stress-induced regional wall motion abnormalities (A), but may exhibit pulmonary congestion (B), reduced myocardial functional reserve (C), altered coronary microcirculation (D) and cardiac autonomic dysfunction (E).

Abstract 1675 Figure. The positivity rate of ABCDE criteria

P4981The reduction of coronary flow velocity reserve in heart failure with reduced, mid-range or preserved ejection fraction

Background

Coronary microvascular disease has been described in heart failure (HF) in presence of angiographically normal epicardial coronary arteries. The prevalence of a reduction of coronary flow velocity reserve (CFVR) in different types of HF and its link with left ventricular contractile reserve (LVCR) is unclear.

Aim

To assess CFVR and LVCR in HF.

Methods

In a prospective, observational, multicenter study, we recruited 380 patients (234 male, 61%, age 66±11 years): 143 (38%) with HF and reduced (<40%) ejection fraction (HFrEF); 98 (26%) with HF and mid-range (40–50%) ejection fraction (HFmrEF); 139 (36%) patients with HF and preserved (>50%) ejection fraction (HFpEF). A control group of 52 asymptomatic patients (23 male, 44%, age 61±14 years) referred to testing for screening was also selected (Controls). All patients underwent dipyridamole (0.84 mg/kg) stress echocardiography in 12 accredited laboratories of 3 countries (Argentina, Brazil and Italy). CFVR was calculated as the stress/rest ratio of diastolic peak flow velocity pulsed-Doppler assessment of left anterior descending (LAD) artery flow. We assessed left ventricular contractile reserve (LVCR) based on global LV Force (systolic blood pressure/end-systolic volume).

Results

Reduced (≤2.0) CFVR was observed in 0/52 controls (0%); 25/139 HFpEF (18%); 28/98 HFmrEF (29%); 78/143 HFrEF (54%, p<0.001 vs all other groups). CFVR was highest in controls (2.80±0.57), lower in HFpEF (2.51±0.57) and HFmrEF (2.26±0.44), lowest in HFrEF (2.04±0.48, p<0.001 vs all other groups). The correlation with LVCR was absent in controls (r=0.098, p=0.491) and HFmrEF (r=0.032, p=0.756), present in HFrEF (r=0.375, p<0.001) and HFpEF (r=0.314, p<0.001).

LVCR vs CFVR

Conclusions

CFVR is frequently abnormal in all types of HF, although more frequently and more profoundly in HFrEF. CFVR mirrors contractile reserve in HFrEF and - less tightly - in HFpEF.

P4984The functional and coronary anatomic correlates of coronary flow velocity reserve during stress echocardiography

Background

The assessment of coronary flow velocity reserve (CFVR) on left anterior descending coronary artery (LAD) expands the risk stratification potential of stress echocardiography (SE) based on regional wall motion abnormalities (RWMA).

Aim

To assess the feasibility and functional correlates of CFVR.

Methods

In a prospective, observational, multicenter study, we initially screened 3,410 patients (2061, 60%, male; age 63±11 years; ejection fraction, EF=61±9%) with known or suspected coronary artery disease (CAD) and/or heart failure (HF). All patients underwent SE (exercise, n=1288; vasodilator, n=1860; dobutamine, n=262) based on RWMA in 20 accredited laboratories of 8 countries. CFVR was calculated as the stress/rest ratio of diastolic peak flow velocity pulsed-Doppler assessment of LAD flow. We also assessed B-lines (a sign of pulmonary congestion) with lung ultrasound and left ventricular contractile reserve (LVCR) based on Force (systolic blood pressure/end-systolic volume).

Results

The success rate for CFVR on LAD was 3,002/3,410 (feasibility=88%): 1,025/1,288 for exercise (80%), 1,766/1,860 (95%) for vasodilator (dipyridamole, n=1,841 and adenosine= 18) and 211/262 (81%) for dobutamine (p<0.001 vs vasodilator, p=NS vs exercise). Imaging time was <3 min and analysis time <1 min per patient. Reduced (≤2.0) CFVR was found in 896/3,002 (30%) patients. At multivariate logistic regression analysis, age (odds ratio, OR: 1.025, 95% Confidence intervals, CI: 1.015–1.036, p<0.001), diabetes (OR: 2.271, 95% CI: 1.218–4.235, p=0.10), RWMA (OR: 6.550, 95% CI: 4.989–8.599, p<0.01), abnormal LVCR (OR: 3.446, 95% CI: 2.774–4.281, p<0.01) and stress-rest B-lines change (OR: 1.519, 95% CI: 1.174–1.99, p=0.01) were associated with reduced CFVR. In the 1149 patients with coronary angiographic information, a reduced CFVR was present in 103/455 patients (23%) with no CAD, 119/432 (27%) with 1-, 72/167 (43%) with 2-, and 62/95 (65%) with 3-vessel disease (p<0.001 by ANOVA for trend).

Figure 1

Conclusions

CFVR is feasible with all SE protocols. The reduced CFVR is often accompanied by RWMA, abnormal LVCR and pulmonary congestion during stress.

Quality control of B-lines analysis in stress Echo 2020

BACKGROUND

The effectiveness trial "Stress echo (SE) 2020" evaluates novel applications of SE in and beyond coronary artery disease. The core protocol also includes 4-site simplified scan of B-lines by lung ultrasound, useful to assess pulmonary congestion.

PURPOSE

To provide web-based upstream quality control and harmonization of B-lines reading criteria.

METHODS

60 readers (all previously accredited for regional wall motion, 53 B-lines naive) from 52 centers of 16 countries of SE 2020 network read a set of 20 lung ultrasound video-clips selected by the Pisa lab serving as reference standard, after taking an obligatory web-based learning 2-h module ( http://se2020.altervista.org ). Each test clip was scored for B-lines from 0 (black lung, A-lines, no B-lines) to 10 (white lung, coalescing B-lines). The diagnostic gold standard was the concordant assessment of two experienced readers of the Pisa lab. The answer of the reader was considered correct if concordant with reference standard reading ±1 (for instance, reference standard reading of 5 B-lines; correct answer 4, 5, or 6). The a priori determined pass threshold was 18/20 (≥ 90%) with R value (intra-class correlation coefficient) between reference standard and recruiting center) > 0.90. Inter-observer agreement was assessed with intra-class correlation coefficient statistics.

RESULTS

All 60 readers were successfully accredited: 26 (43%) on first, 24 (40%) on second, and 10 (17%) on third attempt. The average diagnostic accuracy of the 60 accredited readers was 95%, with R value of 0.95 compared to reference standard reading. The 53 B-lines naive scored similarly to the 7 B-lines expert on first attempt (90 versus 95%, p = NS). Compared to the step-1 of quality control for regional wall motion abnormalities, the mean reading time per attempt was shorter (17 ± 3 vs 29 ± 12 min, p < .01), the first attempt success rate was higher (43 vs 28%, p < 0.01), and the drop-out of readers smaller (0 vs 28%, p < .01).

CONCLUSIONS

Web-based learning is highly effective for teaching and harmonizing B-lines reading. Echocardiographers without previous experience with B-lines learn quickly.

Common dysregulated pathways in obese adipose tissue and atherosclerosis

Background

The metabolic syndrome is becoming increasingly prevalent in the general population that is at simultaneous risk for both type 2 diabetes and cardiovascular disease. The critical pathogenic mechanisms underlying these diseases are obesity-driven insulin resistance and atherosclerosis, respectively. To obtain a better understanding of molecular mechanisms involved in pathogenesis of the metabolic syndrome as a basis for future treatment strategies, studies considering both inherent risks, namely metabolic and cardiovascular, are needed. Hence, the aim of this study was to identify pathways commonly dysregulated in obese adipose tissue and atherosclerotic plaques.

Methods

We carried out a gene set enrichment analysis utilizing data from two microarray experiments with obese white adipose tissue and atherosclerotic aortae as well as respective controls using a combined insulin resistance-atherosclerosis mouse model.

Results

We identified 22 dysregulated pathways common to both tissues with p values below 0.05, and selected inflammatory response and oxidative phosphorylation pathways from the Hallmark gene set to conduct a deeper evaluation at the single gene level. This analysis provided evidence of a vast overlap in gene expression alterations in obese adipose tissue and atherosclerosis with Il7r, C3ar1, Tlr1, Rgs1 and Semad4d being the highest ranked genes for the inflammatory response pathway and Maob, Bckdha, Aldh6a1, Echs1 and Cox8a for the oxidative phosphorylation pathway.

Conclusions

In conclusion, this study provides extensive evidence for common pathogenic pathways underlying obesity-driven insulin resistance and atherogenesis which could provide a basis for the development of novel strategies to simultaneously prevent type 2 diabetes and cardiovascular disease in patients with metabolic syndrome.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-016-0441-2) contains supplementary material, which is available to authorized users.

Identification of matrix metalloproteinase-12 as a candidate molecule for prevention and treatment of cardiometabolic disease

Obesity is strongly associated with metabolic syndrome, a combination of risk factors that predispose to the development of the cardiometabolic diseases: atherosclerotic cardiovascular disease and type 2 diabetes mellitus. Prevention of metabolic syndrome requires novel interventions to address this health challenge. The objective of this study was the identification of candidate molecules for the prevention and treatment of insulin resistance and atherosclerosis, conditions that underlie type 2 diabetes mellitus and cardiovascular disease, respectively. We used an unbiased bioinformatics approach to identify molecules that are upregulated in both conditions by combining murine and human data from a microarray experiment and meta-analyses. We obtained a pool of eight genes that were upregulated in all the databases analysed. This included well known and novel molecules involved in the pathophysiology of type 2 diabetes mellitus and cardiovascular disease. Notably, matrix metalloproteinase 12 (MMP12) was highly ranked in all analyses and was therefore chosen for further investigation. Analyses of visceral and subcutaneous white adipose tissue from obese compared to lean mice and humans convincingly confirmed the up-regulation of MMP12 in obesity at mRNA, protein and activity levels. In conclusion, using this unbiased approach an interesting pool of candidate molecules was identified, all of which have potential as targets in the treatment and prevention of cardiometabolic diseases.

Carotid Stenting with Cerebral Protection: First Clinical Experience Using the PercuSurge GuardWire System

Purpose:

To study the feasibility and safety of carotid angioplasty and stenting using a new cerebral protection device that temporarily occludes the distal internal carotid artery (ICA).

Methods:

Forty-eight high-risk patients (39 men, mean age 69.1 ± 8 years, range 54 to 86) with 53 ICA stenoses underwent percutaneous angioplasty and stenting via the femoral approach under cerebral protection afforded by a 0.014-inch GuardWire balloon occlusion device. Mean stenosis was 82.1% ± 9.65% (range 70 to 96) and mean lesion length was 16.0 ± 7.5 mm (range 6 to 50). Thirty-three (62%) lesions were calcified, and 38 (72%) were ulcerated. Thirty-two (60%) of the lesions were asymptomatic. With the occlusion balloon inflated in the distal ICA, the lesion was dilated and stented. The area was cleaned by aspiration and flushed via an aspiration catheter advanced over the wire. Blood samples were collected from the external carotid artery (ECA) and analyzed to measure the size and number of particles collected. Computed tomography and neurological examinations were performed the day after the procedure.

Results:

Immediate technical success was achieved in all patients with the implantation of 38 Palmaz stents, 8 Expander stents, and 11 Wallstents. Carotid occlusion was well tolerated in all patients but 1 who had multiple, severe carotid lesions and poor collateralization. Mean cerebral flow occlusion time was 346 ± 153 seconds during predilation and 303 ± 143 seconds during stent placement. Total mean flow occlusion time was 542 ± 243 seconds. One immediate neurological complication (transient amaurosis) occurred in a patient who had an anastomosis between the external carotid (EC) and ICA territories. Debris was removed in all patients with a mean 0.8-mm diameter catheter.

Conclusion:

Cerebral protection with the GuardWire device is easy, safe, and effective in protecting the brain from cerebral embolism. Larger studies are warranted.

The Hydrolyser Thrombectomy Catheter: A Single-Center Experience

Purpose:

To present a single-center experience with a mechanical hydrodynamic thrombectomy system (Hydrolyser) in native arteries, veins, and bypass grafts.

Methods:

The Hydrolyser is a 7F, double lumen, over-the-wire thrombectomy catheter. The device was used in 41 patients (22 males; mean age 68 years, range 40 to 90), with recent thromboses (aged 1 to 30 days, mean 8.7 ± 8.5), measuring from 4 to 35 cm long (mean 17.7 ± 9.5). The occlusions were located in native lower limb arteries (n = 28), bypass grafts (n = 8), superior venae cavae (n = 2), axillary vein (n = 1), and pulmonary arteries (n = 2).

Results:

Immediate technical success (residual clot < 50% of lumen diameter) was achieved in 34 patients (83%): 22/28 native arteries (78%), 7/8 bypass grafts (87%), and all pulmonary arteries, superior venae cavae, and the axillary vein. The 7 failed patients were treated surgically (bypass graft or Fogarty balloon). Adjunctive procedures were used to maximize luminal diameter: angioplasty (n = 29, with 13 immediate stent implantations), thromboaspiration (n = 17), and thrombolysis (n = 10). One case of distal embolism was the only complication (treated by thromboaspiration). At 30 days, 30 (73%) vessels remained patent.

Conclusions:

The Hydrolyser system is a promising concept for percutaneous thrombectomy. It is a quick, reliable, efficient device that may offer an alternative to thrombolysis and surgical thrombectomy.

Percutaneous Endoluminal Treatment of Iliac Occlusions: Long-Term Follow-up in 105 Patients

Purpose:

To evaluate the long-term results of percutaneous recanalization techniques in occluded iliac arteries.

Methods:

Percutaneous recanalization was attempted in 105 patients (97 men; mean age 56 years, range 34 to 80) with iliac occlusions using thrombolysis (n = 15), excimer laser (n = 4), mechanical thrombectomy (n = 16), balloon angioplasty alone (n = 23), and angioplasty plus stenting (n = 69). The majority of lesions (n = 72) were in the common iliac artery (CIA); 33 were in the external iliac artery (EIA).

Results:

The primary recanalization rate was 88% (92/105) independent of location (EIA: 90%, CIA: 86%) and lesion length, but dependent on age of thrombus (< 3 months: 100%, > 3 months: 79%, p < 0.02). Complications included 5 (4.8%) cases of distal embolism treated by thromboaspiration or Fogarty balloon embolectomy. Seven (6.7%) early thromboses were treated surgically. Primary and secondary patency rates were calculated at 6 years for all 105 cases and for the 92 recanalized lesions using life-table analysis. Overall, primary patency was 52% (CIA: 58%, EIA: 34%) and secondary 66% (CIA: 74%, EIA: 40%). Lesions < 6 cm had a primary patency of 70%, while those > 6 cm had a 31% rate (p < 0.01). Secondary patencies were 86% and 42%, respectively (p < 0.01). Among recanalized lesions, the primary patency was 61% (CIA: 69%, EIA: 38%) and secondary 77% (CIA: 88%, EIA: 45%; p < 0.05). Lesions < 6 cm had a primary patency rate of 72%, while longer lesions had a primary rate of 44% (p < 0.04); secondary patencies were 89% and 59%, respectively (NS). Primary patency without stent was 57% and with stent 65% (NS); secondary patency without stent was 71% and with stent 82% (NS).

Conclusions:

Percutaneous recanalization of iliac occlusions represents a true alternative to vascular surgery and a first-line treatment option. Stents have a tendency to improve long-term results and are recommended for routine use in chronic iliac occlusions.

Non-randomized, prospective, multi-centre evaluation of the ABSOLUTE .035 peripheral self-expanding stent system for occluded or stenotic superficial femoral or proximal popliteal arteries (ASSESS Trial): acute and 30-day results

AIM

The aim of the paper was to investigate the performance of the ABSOLUTE .035 Peripheral Self-Expanding Stent System in preventing restenosis of superficial femoral or proximal popliteal arteries. Due to a lack of large controlled trials proving its long-term durability femoropopliteal artery stenting is still a matter of debate. In this paper we report the study design, the acute and short-term results of a prospective European registry on the treatment of TASC B and C femoropopliteal lesions with the use of the ABSOLUTE stent.

METHODS

This prospective, non-randomized, multi-centre study enrolled 122 patients with symptomatic peripheral occlusive disease at 14 sites in Europe. Patients were included with obstructed femoropopliteal arteries. Key inclusion criteria were de novo lesions > or = 4.0 mm and < or = 7.0 mm in diameter, and > or = 40 mm and < or = 200 mm in length. Single target vessel treatment had to be performed with a maximum of three stents.

RESULTS

Mean target lesion length was 108 +/- 44 mm (range 22.2 to 200 mm) and mean reference vessel diameter 4.6 +/- 0.8 mm by quantitative angiography; 71% of the lesions analyzable by quantitative angiography (QA) had total occlusions. A total of 227 stents were implanted, 224 of which were deployed successfully (98.7%). Mean percentage of diameter stenosis was reduced from 90.9 +/- 15.5 % (range 41.3 to 100) to 19.0 +/- 8.4% (range 2.3 to 41.5). Device and procedural success were 83.6% each whereas technical success reached 100%. Sixteen lesions had a > or = 30% residual stenosis post-procedure, 6 of them (37.5%) rated as being calcified. Eleven patients experienced major complications (9.1%) and 6 patients experienced minor complications (5%) within 30 days. Duplex ultrasound based 1-month restenosis rate was 9.3%. Target lesion revascularization (TLR) and target vessel revascularization (TVR) rates were 0.8% and 1.7%, respectively and amputation rate was 0.8%. Mean ankle-brachial index (ABI) at rest and after exercise increased significantly from baseline to 30 days follow-up by 0.63 +/- 0.20 to 0.94 +/- 0.17 and from 0.44 +/- 0.23 to 0.85 +/- 0.21, respectively (P<0.001 each).

CONCLUSION

The treatment of TASC B and C femoro-popliteal lesions with use of the ABSOLUTE stent is safe and feasible. Short-term follow-up documents persistent improvement of hemodynamics. The 6- and 12-month data have to be awaited for further conclusions:

Detection of antibodies against spotted fever group Rickettsia (SFGR), typhus group Rickettsia (TGR), and Coxiella burnetii in human febrile patients in the Philippines

A total of 157 sera from febrile patients in the Philippine General Hospital in Manila, Luzon, and the Northern Samar Provincial Hospital, the Philippines, were used. Serum antibodies against spotted fever group Rickettsia (SFGR) and typhus group Rickettsia (TGR) were detected by indirect immunofluorescence test. Antibody positive rates were 1.3% for SFGR (Rickettsia japonica) and 2.5% for TGR (R. typhus), respectively. Rickettsial antibodies in humans in the Philippines were found for the first time. These results underscore the need for further epidemiological study of clinical rickettsioses in the Philippines.

Current status of carotid bifurcation angioplasty and stenting based on a consensus of opinion leaders

OBJECTIVE

Carotid bifurcation angioplasty and stenting (CBAS) has generated controversy and widely divergent opinions about its current therapeutic role. To resolve differences and establish a unified view of CBAS' present role, a consensus conference of 17 experts, world opinion leaders from five countries, was held on November 21, 1999.

METHODS

These 17 participants had previously answered 18 key questions on current CBAS issues. At the conference these 18 questions and participants' answers were discussed and in some cases modified to determine points of agreement (consensus), near consensus, (prevailing opinion), or divided opinion (disagreement).

RESULTS

Conference discussion added two modified questions, placing a total of 20 key questions before the participants, representing four specialties (interventional radiology, seven; vascular surgery, six; interventional cardiology, three; neurosurgery, one). It is interesting that consensus was reached on the answers to 11 (55%) of 20 of the questions, and near consensus was reached on answers to 6 (30%) of 20 of the questions. Only with the answers to three (15%) of the questions was there persisting controversy. Moreover, both these differences and areas of agreement crossed specialty lines. Consensus Conclusions: CBAS should not currently undergo widespread practice, which should await results of randomized trials. CBAS is currently appropriate treatment for patients at high risk in experienced centers. CBAS is not generally appropriate for patients at low risk. Neurorescue skills should be available if CBAS is performed. When cerebral protection devices are available, they should be used for CBAS. Adequate stents and technology for performing CBAS currently exist. There were divergent opinions regarding the proportions of patients presently acceptable for CBAS treatment (<5% to 100%, mean 44%) and best treated by CBAS (<3% to 100%, mean 34%). These and other consensus conclusions will help physicians in all specialties deal with CBAS in a rational way rather than by being guided by unsubstantiated claims.

Percutaneous endovascular treatment of peripheral aneurysms

BACKGROUND

To evaluate the feasibility and efficacy of percutaneous endovascular treatment of peripheral aneurysms.

METHODS

Forty-eight patients, M: 41, F: 7, mean age: 65.7 +/- 10.1 years (47-85 years), with 50 aneurysms were treated: 45 with covered stents (Cragg/Passager 22, Corvita 21, Wallgraft 1, Endotex 1) 4 with non-covered stents and 1 with stent graft. Twenty-six aneurysms located at the iliac artery, 12 at the femoral and 12 at the popliteal artery. Mean lesion length: 61.1 +/- 21.3 mm. Percutaneous approach used in all cases, femoral antegrade (n=24), retrograde (n=23), contralateral (n=2), popliteal (n=1). Stents used were 6-12 mm in diameter and 30-120 mm in length. Multiple stents used to cover all lesions in 20 cases.

RESULTS

Immediate technical success was 96% (48/50). In 1 case of long, tortuous femoropopliteal aneurysm, it was impossible to cover the low part, due to rigidity of the device used, in 1 case of large iliac aneurysm there was incomplete immediate exclusion. No complication during the procedure. Four patients developed non-infectious fever/local pain. Eight thromboses occurred: 2 at iliac, 1 at femoral and 5 at the popliteal level. All other stents remained patent, the aneurysms completely excluded over a mean follow-up of 20.6 +/- 13.2 m, maximum 61 m. Primary patency: all lesions 82%, iliac 92%, femoropopliteal 78%. Secondary patency: all lesions 88%, iliac 96%, femoropopliteal 86%.

CONCLUSION

Percutaneous endoluminal treatment of peripheral aneurysms seems safe and effective with high technical success and good long-term results, except for popliteal localization. It could be an alternative to surgery.

State of the art: which stent for which lesion in peripheral interventions?

Applications of endovascular procedures have been expanded dramatically throughout the human body for both occlusive and aneurysmal disease; arteries at the aortoiliac and femoropopliteal levels are no exception. Currently, interventional procedures are the 1st treatment option for most patients who have peripheral artery disease. Although balloon angioplasty alone offers good immediate and long-term results, the addition of stents has been proposed to improve the procedural success of angioplasty and extend its application to more patients with vascular disease. Stenting, however, is controversial. Its use is considered acceptable in the aortoiliac vessels but is more in dispute for the femoropopliteal vessels. Moreover, the rapid development of endovascular stents for peripheral applications has made stent selection a complicated task for clinical practitioners. Many factors influence the type of stent selected; therefore, knowledge of the stents available--including various designs and individual properties--is mandatory. Appropriate selection depends on adequate preprocedural evaluation of the lesion; the choice of approach; the choice of primary versus selective stent placement; the location and characteristics of the lesion; the availability of stents in the intervention suite; and the experience of the operator Several stents are now available, but they are not equivalent; it is important to select the stent that is best suited to the lesion. On the basis of our experience using different types of stents, as well as our review of the world medical literature, we summarize the properties of various stents and specific indications for their application. This report is intended for use as a practical guide to stent selection.

Angioplasty and stenting of the extracranial carotid arteries

We performed percutaneous transluminal angioplasty and stenting in patients with carotid artery stenosis to determine the efficacy of these techniques as an alternative to surgical endarterectomy. From April 1995 through July 1999, 315 carotid angioplasty procedures were performed (right, 151; left, 164) in 290 patients ranging in age from 40 to 93 years. Of these patients, 42% were symptomatic and 58% were asymptomatic. Twenty-five patients underwent bilateral procedures. The mean percentage of stenosis was 82.3%+/-8.7% SD. Angioplasty and stenting were performed without cerebral protection in 165 arteries and with protection in 150. Two methods of protection were used: the Theron technique and the PercuSurge Guardwire temporary occlusion and aspiration system. Balloon dilation and stent placement were successful in 289 patients; in the last patient, severe arterial tortuosity prevented catheterization and stenting. We observed 13 periprocedural neurologic complications due to ischemia (4.2%): 4 transient ischemic attacks (1.3%), 4 minor strokes (1.3%), and 5 major strokes (1.6%), including 1 death. At 6 months, 210 patients had a follow-up angiogram (155) or duplex ultrasound (55). There were 10 restenoses (4.7%), 1 of which was symptomatic and 2 of which showed mild compression of a Palmaz stent without marked stenosis. Primary and secondary 4-year patency rates were 96% and 99%, respectively. These results demonstrate acceptable mortality and morbidity rates related to carotid angioplasty and stenting. However, we found the risk of embolic stroke to be substantial. Cerebral protection may improve the results of carotid angioplasty and expand the indications for this procedure.

Carotid stenting with cerebral protection: first clinical experience using the PercuSurge GuardWire system

PURPOSE

To study the feasibility and safety of carotid angioplasty and stenting using a new cerebral protection device that temporarily occludes the distal internal carotid artery (ICA).

METHODS

Forty-eight high-risk patients (39 men, mean age 69.1 +/- 8 years, range 54 to 86) with 53 ICA stenoses underwent percutaneous angioplasty and stenting via the femoral approach under cerebral protection afforded by a 0.014-inch GuardWire balloon occlusion device. Mean stenosis was 82.1% +/- 9.65% (range 70 to 96) and mean lesion length was 16.0 +/- 7.5 mm (range 6 to 50). Thirty-three (62%) lesions were calcified, and 38 (72%) were ulcerated. Thirty-two (60%) of the lesions were asymptomatic. With the occlusion balloon inflated in the distal ICA, the lesion was dilated and stented. The area was cleaned by aspiration and flushed via an aspiration catheter advanced over the wire. Blood samples were collected from the external carotid artery (ECA) and analyzed to measure the size and number of particles collected. Computed tomography and neurological examinations were performed the day after the procedure.

RESULTS

Immediate technical success was achieved in all patients with the implantation of 38 Palmaz stents, 8 Expander stents, and 11 Wallstents. Carotid occlusion was well tolerated in all patients but 1 who had multiple, severe carotid lesions and poor collateralization. Mean cerebral flow occlusion time was 346 +/- 153 seconds during predilation and 303 +/- 143 seconds during stent placement. Total mean flow occlusion time was 542 +/- 243 seconds. One immediate neurological complication (transient amaurosis) occurred in a patient who had an anastomosis between the external carotid (EC) and ICA territories. Debris was removed in all patients with a mean 0.8-mm diameter catheter.

CONCLUSION

Cerebral protection with the GuardWire device is easy, safe, and effective in protecting the brain from cerebral embolism. Larger studies are warranted.

Stents in the treatment of renal artery stenosis: long-term follow-up

PURPOSE

To evaluate the role of percutaneous stenting in the treatment of renal arterial lesions after failure of balloon angioplasty.

METHODS

Two hundred ten patients (139 males; mean age 67.7 +/- 9.9 years, range 27 to 87) had 259 balloon-expandable stents (165 Palmaz and 94 Renal Bridge stents) implanted in 244 renal artery stenoses (171 ostial and 73 nonostial lesions). The patients were suffering from intractable hypertension (n = 210) and/or renal dysfunction (n = 48). The majority of the lesions (n = 234) were atheromatous in origin. Stents were implanted for suboptimal balloon dilation (n = 182, 75%), restenotic lesions (n = 27, 11%), or dissection (n = 9, 4%); 26 (11%) ostial lesions were stented primarily. Mean lesion length was 11.9 +/- 4.4 mm (range 5 to 30) and mean percent stenosis was 81.9% +/- 8.25% (range 70 to 100).

RESULTS

Immediate technical success was 99% (241 of 244). Three (1.2%) major complications included one intraprocedural stent thrombosis, one arterial perforation manifesting as a perirenal hematoma 24 hours after the procedure, and one renal arterial rupture. Follow-up over a mean 25.4 +/- 22.8 months (range 1 to 96) in 185 eligible patients (209 arteries) found 24 cases of restenosis (11.4%). Primary and secondary patencies for all lesions at 60 months were 79% and 98%, respectively, with no significant differences between ostial and nonostial lesions or stent types. Hypertension was reversed in 35 (19%), improved in 112 (61%), and remained unchanged in 37 (20%). Renal function was improved in 29% (14 of 48), unchanged in 67% (32 of 48), and worse in 4% (2 of 48).

CONCLUSIONS

Renal artery stenting is safe, effective, and may be an alternative to surgery, particularly in ostial lesions. Our experience shows reduction in the restenosis rate compared to conventional angioplasty. All ostial stenoses should be stented.

Percutaneous transluminal angioplasty of the subclavian arteries

PURPOSE

To review the feasibility, risks, and long-term results of subclavian artery angioplasty with and without Palmaz stent placement.

METHODS

Over a 9-year period, 113 patients (67 males; mean age 63 +/- 13 years) underwent percutaneous balloon angioplasty of subclavian occlusive lesions for a variety of indications: vertebrobasilar insufficiency (n = 70), upper limb ischemia (n = 50), coronary steal syndrome (n = 6), or anticipated coronary artery bypass grafting using the internal mammary artery in 12 asymptomatic patients. There were 94 (83%) stenoses and 19 (17%) occlusions with a mean percent stenosis of 80.1% +/- 7.4% (range 70 to 100). Mean lesion length was 24 +/- 8 mm (range 10 to 50). Beginning in 1989, stents were implanted for suboptimal dilation; in 1995, stenting became routine.

RESULTS

Overall, 103 (91%) of 113 lesions were successfully treated; 10 (53%) occlusions could not be recanalized. Fifty-one stents were implanted in 46 patients. There were 3 (2.6%) procedural complications: a transient ischemic attack, one major (fatal) stroke, and an arterial thrombosis 24 hours after the procedure (treated medically) (0.9% major stroke and death rate). During a mean 4.3-year follow-up (range to 10), 16 (15.5%) restenoses were treated with angioplasty (n = 4), stenting (n = 7), or surgery (n = 5). Primary and secondary patencies for all treated lesions (n = 113) at 8 years were 75% and 81%, respectively; in patients without initial stent placement, the rates were 69% and 76%, while in those with stents, the rates rose slightly to 87% and 94% at 2.5 years (NS). Patency rates for all 103 recanalized lesions were 83% and 90% at 8 years (81% and 90% without stent and 87% and 94% with stent at 2.5 years, respectively [NS]).

CONCLUSIONS

Balloon angioplasty with or without stenting is safe and effective for treating subclavian artery occlusive diseases with good long-term patency. Recanalization of occlusions is more difficult to achieve. Stents (implanted only for suboptimal dilation) do not seem to improve long-term patency.