Association Between Atherosclerotic Aortic Plaques and Left Ventricular Hypertrophy in Patients With Cerebrovascular Events

Estimate of ischemic stroke prevalence according to a novel 4-tiered classification of left ventricular hypertrophy: insights from the general Chinese population

BACKGROUND

Recently, a novel 4-tiered classification of left ventricular hypertrophy (LVH) based on ventricular dilatation (indexed LV end-diastolic volume [EDV]) and concentricity (mass/EDV^0.67) has improved all-cause and cardiovascular mortality risk stratification. However, their possible association with ischemic stroke has not been extensively evaluated in the general population.

METHODS

We evaluated a cross-sectional study of 11,037 subjects from the general population of China in whom echocardiographic and ischemic stroke data were available to subdivide patients with LVH into four geometric patterns: indeterminate, dilated, thick and both thick and dilated hypertrophy.

RESULTS

Compared with normal LV geometry, indeterminate and thick hypertrophy showed a higher prevalence of ischemic stroke (p < .05). Ischemic stroke was significantly greater in participants with indeterminate (adjusted odd ratio [OR]:1.635, 95% confidence interval [CI]: 1.115-2.398) and thick (2.143 [1.329-3.456]) hypertrophy but not significantly in those with dilated (1.251 [0.803-1.950]) and both thick and dilated hypertrophy (0.926 [0.435-1.971]) compared with normal geometry in multivariable analysis.

CONCLUSIONS

Indeterminate and thick hypertrophy were significantly associated with the presence of ischemic stroke in the general Chinese population. The new 4-tiered categorization of LVH can permit a better understanding of which subjects are at high enough risk for ischemic stroke to warrant early targeted therapy. Key messages This was the first study to investigate whether a 4-tiered classification of LVH defines subgroups in the general population that are at variable risks of ischemic stroke. We identified that thick hypertrophy carried the greatest odd for ischemic stroke, independently of traditional risk factors, followed by indeterminate hypertrophy. The new 4-tiered categorization of LVH emerged as a valuable operational approach, a potential alternative to LVM, to refine ischemic stroke stratification in general population.

[Atherosclerosis and coronary artery disease in Senegal: an autopsy series of 116 african patients at Aristide Le Dantec Hospital (Dakar-Senegal)]

OBJECTIVE

To study the prevalence of atherosclerosis (aortic and coronary lesions) in Senegalese people, to determine main risks factors and morphological patterns.

METHODS

A prospective autopsy study was conducted in the pathology department of Aristide Le Dantec Hospital (Dakar-Senegal) where 116 specimens aged over 5 years old were studied.

RESULTS

Autopsy study of 116 Senegalese specimens for atherosclerotic lesions revealed aortic lesions in 100 cases (86%), aortic and coronary lesions both in 48 cases. There were 88 men versus 12 women. The median age was 37.1 years comprised 5 to 77 years old. Hypertensive, smoking and abdominal obesity were detected respectively in 5 cases, 37 cases and 33 cases. In aortic vessel, the main lesions detected were severe fibrous plaques detected in 40 cases. In coronary arteries, fibrous plaques were detected in 18 cases, severe fibrous plaques in 17 cases.

CONCLUSION

Our study in Senegalese population showed existence of atherosclerotic lesions. These lesions were more responsible for complications as myocardial infarction.

Relationship between atherosclerotic risk factors and aortic plaques in patients with first-ever ischaemic stroke

OBJECTIVE

Aortic plaque is considered a risk factor of ischaemic stroke, and both ulceration and plaque thickness are considered important. However, the relative importance of aortic plaque and carotid plaque remains unclear. The purpose of this study is to clarify the relation between aortic and carotid plaque lesions and atherosclerotic risk factors in patients with acute ischaemic stroke.

METHODS

We enrolled 76 patients with first-ever ischaemic stroke, undergoing transoesophageal echocardiography, whose aetiology of ischaemic stroke was unknown. We divided the patients into two groups according to aortic plaque thickness, based on previous reports, i.e., a high-risk group (over 4mm) and a low-risk group (less than 4mm). We also examined several atherosclerotic risk factors.

RESULTS

Mean age, gender and hypertension was not significantly different between the low-risk and high-risk group. HDL-cholesterol (P<0.01), LDL/HDL ratio (P<0.05), non-HDL-cholesterol (P<0.05), HbA1c (P<0.05) and eGFR (P<0.01) were significantly different between the two groups. Max plaque thickness in the carotid artery was correlated with aortic plaque lesions.

CONCLUSION

Multiple atherosclerotic risk factors are associated with greater aortic plaque lesions. Aortic plaque is important not only as an embolic source, but also as one of the atherosclerotic markers.

Carotid artery atherosclerotic profile as a predictor of the aorta atherosclerotic profile in patients with cerebrovascular events

BACKGROUND

It is well known that the presence of atheroma of the thoracic aorta is a risk factor for cerebrovascular events. We sought to evaluate whether the presence and the morphology of atherosclerotic plaque in the carotid artery detected by duplex ultrasonography is associated with disease in the proximal aorta visualized by transesophageal echocardiogram in patients with a cerebrovascular event.

METHODS

We carried out a cross-sectional prospective study including 147 consecutive patients with prior stroke or transient ischemic attack (TIA). Neurological evaluations were performed by an expert neurologist using clinical and tomographic diagnostic criteria including the definition of etiology and whether the patient suffered from stroke or TIA. Transthoracic and transesophageal echocardiograms and carotid artery duplex ultrasonography were performed by the same examiner. Patients with and without plaque in the carotid artery were compared using Student's t test or the χ2 test. Regression analysis was used to determine whether the presence of plaque in the carotid artery was predictive of the presence of plaque in the proximal aorta and to analyze the relationship between the echogenicity of carotid and aortic plaques. The significance level was set at p < 0.05.

RESULTS

All 147 patients (95 men) were included in the analysis. Patients' ages ranged from 23 to 85 years (65 ± 12.4 years). Most of the patients (58.5%) were Caucasian, while 41.5% were African-Brazilian. Arterial hypertension, diabetes and tobacco use were more frequent among patients with atherosclerotic plaque in the aorta. A normal carotid intima-media thickness halved the risk of atherosclerotic plaque in the aorta [odds ratio (OR) 0.46, 95% confidence interval (CI) 0.23-0.91; p = 0.026]. The presence of carotid plaque increased the risk of aortic plaque by 70-fold (OR 73.2, 95% CI 25.6-2,018.6; p < 0.001) in univariate analysis. The absence of atherosclerotic plaque in the carotid artery reduced the risk of plaque in the aorta to almost 0 (OR 0.014, 95% CI 0.004-0.041; p < 0.001). Considering the 86 patients with both aortic and carotid plaques, the presence of hypoechoic plaque in the carotid artery was a predictor of hypoechoic plaque in the aorta (OR 10.1, 95% CI 3.3-31.2; p < 0.001).

CONCLUSIONS

The carotid artery atherosclerotic profile defined by ultrasonography is a strong predictor of the atherosclerotic profile of the proximal aorta. This should be taken into consideration before referring patients with acute cerebrovascular events for transesophageal echocardiogram.

Retrograde blood flow in the aortic arch determined by transesophageal Doppler ultrasound

BACKGROUND

Aortic arch atheromas may be important sources of cerebral embolism. Aortic plaques are frequently found somewhat distal to the origin of the cerebral arteries, implying that cerebral embolization from such plaques depends on local retrograde blood flow components in this area. Therefore, we investigated the occurrence of blood flow reversal in this part of the aorta. Furthermore, since the presence and magnitude of retrograde flow might be influenced by aortic wall properties, we also studied the relationship between plaque size and distribution, aortic strain and degree of retrograde flow.

METHODS

We evaluated aortic arch ante- and retrograde blood flow velocities in 56 patients by transesophageal echocardiography using color-Doppler-guided pulsed-Doppler techniques. The velocity-time integrals (VTI) were measured and the diastolic/systolic VTI ratio was calculated.

RESULTS

Retrograde diastolic blood flow was noted in all subjects, and diastolic/systolic VTI ratios were higher (p < 0.05) in patients with plaque >or=4 mm (n = 17) compared to those (n = 39) without. Patients exhibiting plaques exclusively in the aortic arch showed the highest VTI ratios (p < 0.01) and tended to have the lowest strain values. Aortic strain was also reduced in patients >50 years of age (p < 0.01).

CONCLUSIONS

Our findings demonstrate retrograde aortic flow in all subjects and its proportion increases in subjects with atherosclerosis, particularly in the aortic arch. Aortic plaques situated distally to the origin of the cerebral arteries are therefore possible sources of cerebral emboli.

Association of premature ventricular complexes with central aortic pressure indices and pulse wave velocity

BACKGROUND

Although premature ventricular complex (PVC) occurs frequently, its predisposing factors have rarely been studied. We examined the connection between PVC and aortic stiffness.

METHODS

We recruited 200 consecutive patients (< 50 years, 95 men, mean age 36 +/- 10 years) who received a 24-hour ambulatory electrocardiography examination for palpitation and PVC loads. Muscular artery pulse wave velocity (PWVm) and 4 main aortic pressure indices-augmented pressure, augmentation index (AI(x)), AI(x) corrected for a steady heart rate of 75 beat/min, and the extra workload-were measured, and atherosclerosis risk was evaluated.

RESULTS

Eighty-three (42%) patients had no PVC loads; 58 (29%) patients had low loads (< 24 beat/d), and 59 (29%) had high loads (> or = 24 beat/d). Only age and hyperlipidemia were significantly associated with PVC loads. Using a multivariate logistic regression model adjusted for potential confounders, we found that AI(x) (odds ratio [OR] 1.88, 95% CI 1.20-2.91, P = .005); augmented pressure (OR 1.57, 95% CI 1.02-2.43, P = .042); AI(x) corrected for a steady heart rate of 75 beat/min (OR 1.82, 95% CI 1.18-2.82, P = .007); and PWVm (OR 1.53, 95% CI 1.07-2.19, P = .021) were independent factors for PVC loads.

CONCLUSION

Increased central aortic pressure indices as well as PWVm were associated with increased PVC loads in young patients undergoing 24-hour ambulatory electrocardiography. Central aortic properties probably contributed to the occurrence of PVC.

Differential impact of age, sex, and hypertension on aortic atherosclerosis: the Framingham Heart Study

OBJECTIVE

The purpose of this study was to investigate the impact of age, sex, and hypertension (HTN) on aortic atherosclerotic burden using cardiovascular MRI (CMR) in a free-living longitudinally followed cohort.

METHODS AND RESULTS

1763 participants (829 M and 934 F; 38 to 88 years of age) of the Framingham Heart Study Offspring cohort underwent CMR of the thoracoabdominal aorta using an ECG-gated 2D T2-weighted black-blood sequence. Of these, 1726 subjects (96%) with interpretable CMR were characterized by sex, age-quartile, and presence or absence of HTN and clinical cardiovascular disease (CVD). Aortic plaque prevalence and volume increased with increasing age in both sexes. For the nonhypertensive (no-HTN) group, plaque was identified in 702 (46%) with greater prevalence in women than in men (P<0.006). HTN was associated with greater aortic plaque burden (P<0.02). The 200 subjects with clinical CVD had greater plaque burden than subjects without CVD (P<0.0001).

CONCLUSIONS

In this free-living longitudinally followed cohort, subclinical aortic atherosclerosis was seen in nearly half of subjects and increased with advancing age. HTN was associated with increased aortic plaque burden. Among no-HTN subjects, women had greater plaque burden than men. These data suggest that subclinical atherosclerosis is more common in no-HTN women and emphasize the importance of focusing on preventive measures in both sexes.

Relation between mitral annular calcium and complex aortic atheroma in patients with cerebral ischemia referred for transesophageal echocardiography

Mitral annular calcium (MAC) has been shown to be an independent predictor of stroke, but the basis for this association remains incompletely defined. This study was conducted to investigate the extent to which aortogenic embolism may mediate the MAC-stroke relation. In a cross-sectional study of patients referred for transesophageal echocardiography for the evaluation of cerebral ischemia, the relation between MAC and proximal and distal complex aortic atheroma (CAA) was assessed. In 419 patients composing the study cohort, MAC was associated with atherosclerosis risk factors, previous cardiovascular disease, atrial fibrillation, ipsilateral large-artery stenosis, left-sided cardiac abnormalities, and aortic valve calcium. MAC was associated with CAA of the proximal and distal thoracic aorta in unadjusted analyses, and these associations became stronger with increasing MAC severity. After adjustment for clinical and echocardiographic covariates, MAC exhibited a significant association with proximal and distal CAA in the entire cohort. In patients without alternative potential mechanisms for cerebral ischemia, however, the relation with proximal CAA became more pronounced (adjusted odds ratio 2.74, 95% confidence interval 1.22 to 6.16), but that for distal CAA changed little and became nonsignificant (adjusted odds ratio 1.97, 95% confidence interval 0.87 to 4.45). In conclusion, MAC was significantly associated with proximal and distal CAA independent of clinical and echocardiographic covariates in this cohort with cerebral ischemia, but in subjects without identifiable alternative mechanisms, the magnitude of the relation increased only for proximal CAA. These findings support the role of proximal CAA as a direct mediator of the increased stroke risk associated with MAC.