Background and Purpose— This guideline provides an overview of the evidence on various established and potential stroke risk factors and provides recommendations for the reduction of stroke risk. Methods— Writing group members were nominated by the committee chair on the basis of each writer’s previous work in relevant topic areas and were approved by the American Heart Association Stroke Council’s Scientific Statement Oversight Committee. The writers used systematic literature reviews (covering the time period since the last review published in 2001 up to January 2005), reference to previously published guidelines, personal files, and expert opinion to summarize existing evidence, indicate gaps in current knowledge, and when appropriate, formulate recommendations based on standard American Heart Association criteria. All members of the writing group had numerous opportunities to comment in writing on the recommendations and approved the final version of this document. The guideline underwent extensive peer review before consideration and approval by the AHA Science Advisory and Coordinating Committee. Results— Schemes for assessing a person’s risk of a first stroke were evaluated. Risk factors or risk markers for a first stroke were classified according to their potential for modification (nonmodifiable, modifiable, or potentially modifiable) and strength of evidence (well documented or less well documented). Nonmodifiable risk factors include age, sex, low birth weight, race/ethnicity, and genetic factors. Well-documented and modifiable risk factors include hypertension, exposure to cigarette smoke, diabetes, atrial fibrillation and certain other cardiac conditions, dyslipidemia, carotid artery stenosis, sickle cell disease, postmenopausal hormone therapy, poor diet, physical inactivity, and obesity and body fat distribution. Less well-documented or potentially modifiable risk factors include the metabolic syndrome, alcohol abuse, drug abuse, oral contraceptive use, sleep-disordered breathing, migraine headache, hyperhomocysteinemia, elevated lipoprotein(a), elevated lipoprotein-associated phospholipase, hypercoagulability, inflammation, and infection. Data on the use of aspirin for primary stroke prevention are reviewed. Conclusion— Extensive evidence is available identifying a variety of specific factors that increase the risk of a first stroke and providing strategies for reducing that risk.

Primary Prevention of Ischemic Stroke A Guideline From the American Heart Association/American Stroke Association Stroke Council: Cosponsored by the Atherosclerotic Peripheral Vascular Disease Interdisciplinary Working Group; Cardiovascular Nursing Council; Clinical Cardiology Council; Nutrition, Physical Activity, and Metabolism Council; and the Quality of Care and Outcomes Research Interdisciplinary Working Group: The American Academy of Neurology affirms the value of this guideline.

We examined the relation between the serum total cholesterol level and the risk of death from stroke during six years of follow-up in 350,977 men, 35 to 57 years of age, who had no history of heart attack and were not currently being treated for diabetes mellitus. The diagnosis of stroke and the type of stroke were obtained from death certificates. Using proportional-hazards regression to control for age, cigarette smoking, diastolic blood pressure, and race or ethnic group, we found that the six-year risk of death from intracranial hemorrhage (International Classification of Diseases, ninth edition [ICD-9], categories 431 and 432) was three times higher in men with serum cholesterol levels under 4.14 mmol per liter (160 mg per deciliter) than in those with higher cholesterol levels (P = 0.05 by omnibus test across five cholesterol levels). On the other hand, a positive association was observed between the serum cholesterol level and death from nonhemorrhagic stroke (P = 0.007). The inverse association of the serum cholesterol level with the risk of death from intracranial hemorrhage was confined to men with diastolic blood pressure greater than or equal to 90 mm Hg, in whom death from intracranial hemorrhage is relatively common. We conclude that there is an inverse relation between the serum cholesterol level and the risk of death from hemorrhagic stroke in middle-aged American men, but that its public health impact is overwhelmed by the positive association of higher serum cholesterol levels with death from nonhemorrhagic stroke and total cardiovascular disease (ICD-9 categories 390 through 459).

Serum cholesterol levels and six-year mortality from stroke in 350,977 men screened for the multiple risk factor intervention trial

BACKGROUNDAn improved intravascular ultrasonic Doppler device could aid the clinical assessment of coronary hemodynamics. We evaluated a new device consisting of a 12-MHz piezoelectric transducer integrated onto the tip of a 0.018-in. flexible, steerable angioplasty guide wire.METHODS AND RESULTSDoppler spectra were recorded in model tubes with pulsatile blood flow and in-line electromagnetic flowmeter. In four straight tubes (i.d., 0.79-4.76 mm), the time average of spectral peak velocity (APV) was linearly related to blood flow (QEMF) (r2 greater than or equal to 0.98 for each tube). A Doppler-derived quantitative flow estimate (QD) was calculated as the product of vessel cross-sectional area and mean velocity, with mean velocity estimated as 0.5 x APV. The slope of QD versus QEMF for the four tubes was near unity. APV was less accurate in a 7.94-mm straight tube and in tortuous segments. In four dogs, the left circumflex coronary artery (LCx) was perfused from the femoral artery via a cannula with in-l...

Validation of a Doppler guide wire for intravascular measurement of coronary artery flow velocity.

Background and Purpose— This guideline provides an overview of the evidence on various established and potential stroke risk factors and provides recommendations for the reduction of stroke risk. M...

https://www.ahajournals.org/doi/pdf/10.1161/01.STR.32.1.280

Primary Prevention of Ischemic Stroke A Statement for Healthcare Professionals From the Stroke Council of the American Heart Association

Cardiovascular disease (CVD) prevention in Asia is an important issue for world health, because half of the world’s population lives in Asia. Asian countries and regions such as Japan, the Republic of Korea, the People’s Republic of China, Hong Kong, Taiwan, and the Kingdom of Thailand have greater mortality and morbidity from stroke than from coronary heart disease (CHD), whereas the opposite is true in Western countries.1 The reasons why this specific situation is observed in countries with rapid and early-phase westernization, such as Japan and South Korea, are very interesting.

The Seven Countries Study conducted by Keys et al2 in 1957 found that Japanese populations had lower fat intake, lower serum total cholesterol, and lower CHD than populations in the United States and Scandinavia, in spite of higher smoking rates. The serum total cholesterol level in Japan has increased rapidly since World War II in accordance with an increase in dietary fat intake from 10% of total energy intake per capita per day to 25%.1,2 Despite this increase, the specific characteristic of lower CHD incidence and mortality than that in Western countries has persisted.3,4 Whether Japanese people and certain other Asian populations have different risk factors for CHD than Western populations has been a subject of discussion for quite some time.

In this article, we discuss the existence of higher stroke rates and lower CHD rates in Asian countries than in Western countries and the respective risk factors for this on the basis of extensive reviews of cohort studies. We also discuss whether these risk factors differ from those of Western countries. Along with this, we examine the relationship between serum total cholesterol and total stroke and its subtypes. We also address the emerging problems and important issues for CVD prevention in Asia.

An extensive …

Cardiovascular disease and risk factors in Asia: a selected review.

Multivariate analysis of risk factors for stroke. Eight-year follow-up study of farming villages in Akita, Japan.

Poststenotic blood flowvelocities wereevaluated inninepatients with75%to99% stenosis oftheleft anterior descending coronaryartery (LAD)during coronaryartery bypass graft surgery.We usedthe20MHz 80-channel pulsed Doppler velocimeter developed inourlaboratory. Anoperator placed aspecially designed probe on thenative LAD withhisfingers. Before induction ofextracorporeal circulation, LAD blood velocities were measured atseveral locations distal tothe stenosis. Thepoststenotic flowvelocities wererich insystolic flowcomponent withreduced diastolic component. Thevelocity configuration inthepoststenotic portions was characterized bythepresence ofreverseflowvelocities and/or irregularity ofthevelocity pattern nearthevessel wall, indicating the existence offlowseparation andrecirculation intheregions. Thebroadening ofthevelocity spectrum observed atcentral axial regions suggested theoccurrenceofflowdisturbances. After grafting, the velocity waveform intheLADbeyond aveinbypass graft changed toadiastolic-predominant pattern with arelatively small systolic component. Atransient bypass graft occlusion caused amarked reduction indiastolic flowvelocity. Thesystolic-to-dias

Analysis of flow characteristics inpoststenotic regionsofthehumancoronaryartery during bypass graft surgery

The dose-response relation of contrast medium-induced hyperemic response in coronary blood flow (contrast hyperemia) was investigated to determine the optimal dose of contrast medium (CM, Urografin-76®) for the assessment of coronary flow reserve in man. The great cardiac venous flow (GCVF) was determined with the continuous thermodilution method during the contrast hyperemia induced by the intracoronary injection of CM of three different doses, ie, 2, 4, and 6 ml/60 kg of body weight, into left coronary artery.



Submaximal coronary vasodilation could be obtained by intracoronary injection of 4 ml of CM with minimal changes in systemic hemodynamics. The contrast hyperemia with this dose of CM was reproducible and also closely correlated with that obtained during pacing-induced angina. Thus, we conclude that the contrast hyperemic technique with intracoronary injection of 4 ml of Urografin-76® could be a reliable method to assess the coronary flow reserve.

Validity of contrast hyperemia for clinical assessment of coronary flow reserve: the optimal dose of contrast medium and reproducibility of the technique.

Direct observation and analysis of spatiotemporal dynamics of individual living monocyte during transendothelial migration

The afterload dependency of relaxation rate was reappraised in isolated canine hearts both in isovolumic and isobaric contractions by using the reliable exponential method in which the asymptote LV pressure (P x ) is variable. This method provided a closer correlation (r = 0.999 ± 0.001) between the measured LV pressure decay and the model estimate than the semilogarithmic method assuming P x = 0 (r = 0.992 ± 0.001). Time constants of isovolumic LV pressure decay obtained by the exponential method demonstrated a significant (p<0.01) decrease during volume loading both in isovolumic and isobaric contractions, indicating that the relaxation rate is augmented as afterload increases. In contrast, if we assume P x = 0, the time constant of LV pressure decay was independent of peak LV pressure as previously reported. Thus, we conclude that the load insensitive relaxation rate implied by the semilogarithmic method (P x = 0) may be erroneous due to an invalid assumption, ie, P x = 0, but the relaxation rate is augmented as afterload increases both in isovolumically contracting and isobarically ejecting isolated canine hearts.

Katsuhiko Tsujioka

Papers

Multivariate analysis of risk factors for stroke. Eight-year follow-up study of farming villages in Akita, Japan.

Analysis of flow characteristics inpoststenotic regionsofthehumancoronaryartery during bypass graft surgery

Validity of contrast hyperemia for clinical assessment of coronary flow reserve: the optimal dose of contrast medium and reproducibility of the technique.

Direct observation and analysis of spatiotemporal dynamics of individual living monocyte during transendothelial migration

An increase in afterload augments ventricular relaxation rate in isolated perfused canine hearts.