"How's the traffic?" That's one of the first questions I ask patients who visit my office. But I'm not just making small talk. Being stuck in traffic raises blood pressure and triples heart attack risk. So if a patient has had a tough commute and her BP is elevated, I'll recheck it later.

    There are other surprising situations and times when the chance of heart attack rises dramatically. If you or someone you know has a history of heart trouble, here's when to be watchful:

    First thing in the morning

    The risk of heart attack increases 40% in the morning, Harvard researchers estimate. Why? As you awaken, your body secretes adrenaline and other stress hormones, increasing blood pressure and a demand for oxygen. Your blood is also thicker and harder to pump because you're partially dehydrated. All this taxes the heart. Protect yourself: Build some time into your wake schedule so you can hit the snooze button and wake up slowly. If you're a morning exerciser, warm up thoroughly so as not to additionally stress the heart. And if you're on a beta-blocker, take it before bed so the medication is at full strength in the AM.

    On Monday mornings especially

    Twenty percent more heart attacks occur on this day, probably because people are stressed and depressed about returning to work. Protect yourself: Relax on Sunday, but try not to sleep in. Getting up early on Monday after sleeping late Saturday and Sunday can raise blood pressure even more because your body is fatigued and its natural rhythms are out of whack. Try to maintain a regular sleep/wake schedule all week.

    At the podium

    From the heart's perspective, public speaking can be similar to unaccustomed exercise. Extreme nervousness raises blood pressure, heart rate, and adrenaline levels, all of which can make the presentation itself a secondary worry. Protect yourself: To counter these effects, some of my patients take a betablocker before speaking, flying, or doing anything that makes them overly anxious.

    After a high-fat, high-carb meal

    Studies show these foods constrict blood vessels, making blood more prone to clot. Protect yourself: If you must indulge, keep your portion sizes reasonable. A daily aspirin will also help prevent blood "stickiness."

    During a bowel movement

    Straining increases pressure in the chest, slowing the return of blood to the heart. Protect yourself: Eat lots of fiber, stay hydrated, and avoid straining.

    During vigorous exercise you're unprepared for

    Having a heart attack while shoveling snow is a classic example of this. The heart attack occurs because the victim isn't accustomed to that kind of effort and stress hormones skyrocket, causing blood pressure and heart rate to jump. Protect yourself: Regular exercise protects your heart. But increase your intensity level gradually.

    交通狀況怎樣？"這是我向走進(jìn)我辦公室的患者首先問(wèn)到的問(wèn)題之一。我不僅僅是在閑聊。交通堵塞會(huì)使人血壓升高，心臟病發(fā)作風(fēng)險(xiǎn)提高二倍。所以如果剛經(jīng)歷了交通堵塞，那么她的血壓會(huì)升高，我會(huì)過(guò)一會(huì)再一次檢查血壓。

    還有一些處境和時(shí)間心臟病發(fā)作機(jī)率大幅升高。如果您或您認(rèn)識(shí)的某個(gè)人有心臟病史，那么以下時(shí)間必須當(dāng)心：

    早晨的第一件事

    哈佛研究人員估計(jì)，早晨心臟病發(fā)作的風(fēng)險(xiǎn)增加40%.原因何在？因?yàn)槟鷦偺K醒，身體會(huì)分泌腎上腺素和其它應(yīng)激激素，血壓升高，氧需求量增大。因?yàn)槟�身體部分脫水所以血液較稠，心臟不易將其泵動(dòng)。這些都加重了心臟的負(fù)擔(dān)。自我保護(hù)措施：在您起床時(shí)間表中安排一些時(shí)間，這樣您就可以按下鬧鈴按鈕，慢慢蘇醒。如果您是位晨練者，那么要充分熱身，這樣就不會(huì)給心臟增加另外的壓力。再者，如果您正在服用β受體阻滯劑，那么請(qǐng)?jiān)谒�前服用，這樣藥力在午夜時(shí)最強(qiáng)。

    星期一早晨特別當(dāng)心

    百分之二十以上的心臟病在這一天發(fā)作，這也許是因?yàn)槿藗儗?duì)于又要上班感到緊張和沮喪的緣故。自我保護(hù)：在星期天放松，但盡量不要睡過(guò)頭。星期六和星期天晚睡之后星期一早起可使血壓升得更高，因?yàn)槟�身體疲勞，生理節(jié)奏需要調(diào)整。整個(gè)一周都要保持有規(guī)律的睡眠-覺(jué)醒節(jié)律。

    站講臺(tái)

    從心臟的角度講，公開(kāi)演講與不習(xí)慣的運(yùn)動(dòng)的作用相似。極度緊張使血壓升高，心率加快，腎上腺素水平上升，所有這些可使演講本身成為第二大讓人擔(dān)憂的事情。自我保護(hù)措施：為了對(duì)抗這些作用，我的有些病人在演講、乘飛機(jī)或做任何使他們感到過(guò)分緊張的事情之前服用β受體阻滯劑

    高脂肪、高碳水化合物飲食之后

    研究表明，這些食物收縮血管，使血液更具凝結(jié)的傾向。自我保護(hù)措施：如果您必須吃這些食物，那么請(qǐng)您保持合適的量。每天服用阿司匹林也有助于防止血栓的形成。

    排便過(guò)程中

    過(guò)度用力會(huì)增加胸部壓力，減慢血液流回心臟。自我保護(hù)措施：多吃含纖維的食物，保持大全濕潤(rùn)，避免過(guò)度用力。

    在進(jìn)行沒(méi)有準(zhǔn)備的劇烈運(yùn)動(dòng)過(guò)程中

    患心臟病還鏟雪就是典型例子。心臟病發(fā)作是因?yàn)榛颊邔?duì)此類活動(dòng)不適應(yīng)，應(yīng)激激素直線上升，引進(jìn)血壓和心率猛增。自我保護(hù)措施：經(jīng)常鍛煉會(huì)保護(hù)您的心臟，但鍛煉強(qiáng)度應(yīng)逐漸增加。