Feeds:
Posts
Comments

Posts Tagged ‘heart attack prevention’

In a new story by Megan Brooks over at Medscape, “Gastric Bypass Has Advantages in Less Obese Patients” – the latest news from an Orlando conference confirms what cartagena surgery fans already know; that gastric bypass surgery is a viable and effective option in moderately obese patients (particularly patients with diabetes.)  This is encouraging in the continuing battles between patients and insurance providers.

As we’ve said before – it’s important to treat obesity definitively before patients develop serious and potentially life threatening complications such as diabetes and hypertension, and the sequelae related to this (coronary artery disease, ischemic limbs, stroke, renal failure).

In order to treat this effectively and aggressively, we shouldn’t wait until the problem is out of control.  A patient shouldn’t have to be 600 pounds for the doctors to consider bariatric surgery – we should help people before that.

I’ve re-posted the article below. [italics are mine.]

Gastric Bypass Has Advantages in Less Obese Patients

June 16, 2011 — There are benefits to performing laparoscopic Roux en Y gastric bypass (RYGB) in obese patients who have a body mass index (BMI) below 35 kg/m2, according to a study reported at the American Society for Metabolic and Bariatric Surgery 28th Annual Meeting in Orlando, Florida.

Among patients who underwent the surgery, the rates of remission of type 2 diabetes were higher in those with a BMI below 35 kg/m2 than in those with higher BMIs. The “less obese” patients also lost a greater percentage of their excess weight in the first year after surgery than their peers with higher BMIs.

“The study raises the question of whether early referral leads to better outcomes,” John Morton, MD, director of bariatric surgery at Stanford Hospital & Clinics at Stanford University in Palo Alto, California, and an investigator with the study, noted in a conference statement.

“Bariatric surgery is tremendous for weight loss, but its other big advantage is improving medical problems, in particular type 2 diabetes,” Dr. Morton noted in an interview with Medscape Medical News.

Outcomes Better at Lower BMI

Current guidelines from the National Institutes of Health recommend that gastric bypass be reserved for patients who have a BMI of 35 kg/m2 or higher and an obesity-related condition, or who have a BMI of at least 40 kg/m2.

Dr. Morton’s team took a look back at 980 patients who underwent laparoscopic RYGB at their institution between 2004 and 2010. “We ask patients to lose some weight before surgery because it’s a good way to make sure they are committed to the program, and it makes the surgery a little bit safer,” Dr. Morton said. “Therefore, we had some patients below a BMI of 35 kg/m2 at the time of surgery.”

For the analysis, the patients were grouped according to their presurgery BMI: below 35 kg/m2, 35 to 39.9 kg/m2, 40 to 49.9 kg/m2, and above 50 kg/m2.

“When we examined type 2 diabetes resolution rates, we found that those with the lowest BMI had the best resolution rates,” Dr. Morton reported. All 12 patients with a BMI below 35 kg/m2 no longer had type 2 diabetes after surgery, whereas patients with higher BMIs had remission rates of roughly 75%.

We are looking to entertain the idea that maybe obese patients should have the option of surgical intervention for their diabetes sooner rather than later because, as the study showed, as the BMI gradient goes up, your diabetes resolution rate with surgery goes down,” Dr. Morton said.

The researchers also found that patients with a BMI below 35 kg/m2 who had the surgery had lost more of their excess weight at 3, 6, and 12 months than patients with a higher BMI.

After 1 year, the patients with BMIs below 35 kg/m2 had lost 167% of their excess weight. By comparison, those with a BMI from 35 to 39.9 kg/m2 had lost 112%, those with a BMI from 40 to 49.9 kg/m2 had lost 85%, and those with a BMI above 50 kg/m2 had lost 67% of their excess weight.

Laparoscopic RYGB also took less time in patients with the lowest BMI (170 minutes) than in those with higher BMIs (177 minutes, 182 minutes, and 194 minutes, respectively).

Reevaluation of BMI Guideline Needed

In an interview with Medscape Medical News, John David Scott, MD, a bariatric surgeon at Greenville Hospital System University Medical Center in South Carolina, who was not involved in the study, said that “the BMI level of 35 is an arbitrary standard set many years ago that certainly needs to be reevaluated.”

“Most of the evidence that has been coming out lately has shown not only a positive weight loss benefit for that particular group, but also positive overall health effects,” he added. “In particular, the resolution of diabetes is astounding. To be able to offer patients a surgical cure for their type 2 diabetes is very exciting,” Dr. Scott said.

Dr. Morgan has disclosed no relevant financial relationships. Dr. Scott reports receiving speaker fees from WL Gore & Associates and fellowship support from Ethicon Endo Surgery.

American Society for Metabolic and Bariatric Surgery (ASMBS) 28th Annual Meeting: Abstract P-54. Presented June 16, 2011.

In other news, from the same conference (Megan Brooks reporting) – patients undergoing successful bariatric surgery (with resultant weight loss) had decreased rates of heart attacks and stroke.
“Bariatric Surgery good for the Heart”

June 16, 2011 — Bariatric surgery and the significant weight loss it achieves can  significantly reduce the incidence of myocardial infarction (MI), stroke, and premature death, according to a study presented at the American Society for Metabolic and Bariatric Surgery (ASMBS) 28th Annual Meeting in Orlando, Florida.

“In addition to weight loss, bariatric surgery offers patients a whole host of health benefits, including a reduction in the risk of major cardiovascular problems,” study presenter John David Scott, MD, a bariatric surgeon at Greenville Hospital System University Medical Center in South Carolina, noted in an interview with Medscape Medical News.

“There is a long line of studies showing that bariatric surgery affects cardiovascular outcomes,” Dr. Scott noted. “The difference between our study and other studies is that we looked at major cardiovascular events (heart attack and stroke), whereas a lot of other studies have looked at risk for these events.”

The researchers reviewed data on 9140 morbidly obese individuals, 40 to 79 years of age, who had undergone bariatric surgery (n = 4747), gastrointestinal (GI) surgery (n = 3066), or orthopedic surgery (n = 1327) in South Carolina between 1996 and 2008.

The GI group (hernia or gallbladder) and the orthopedic group (joint replacement) served as control groups because of their similar health and risk profiles, the authors note.

All patients had similar a health status before surgery and no history of MI or stroke. The patients were followed to the end points of first MI, stroke, transient ischemic attack, or death.

“Life-table analysis demonstrated significantly improved event-free survival in the bariatric patients within 6 months of surgery, and it was sustained over time,” the authors note in the meeting abstract.

Five years after surgery, an estimated 85% of bariatric surgery patients were free of MI and stroke, compared with 73% of orthopedic patients and 66% of GI patients, the researchers say.

At 10 years, event-free survival was 77% in the bariatric group, 64% in the orthopedic group, and 62% in the GI group (P < .05).

After adjustment for differences in age and relevant comorbidities, bariatric surgery was an independent predictor of event-free survival. Compared with orthopedic surgery, the hazard ratio (HR) was 0.57 (95% confidence interval [CI], 0.47 to 0.69); compared with GI surgery, the HR was 0.35 (95% CI, 0.29 to 0.43).

“Important Area of Emerging Study”

In a statement from the ASMBS, Anita Courcoulas, MD, MPH, director of minimally invasive bariatric and general surgery at the University of Pittsburgh Medical Center, Pennsylvania, who was not involved in the study, said: “The impact of bariatric surgery on both cardiovascular risk factors and events is an important area of emerging study.”

The findings, she said, are “suggestive of an association between undergoing bariatric surgery and improved event-free survival. This relationship needs to be further explored with prospective clinical data, but still highlights the importance of understanding the broader impact of bariatric surgery on long-term outcomes.”

In an interview with Medscape Medical News, John Morton, MD, director of bariatric surgery at Stanford Hospitals & Clinics at Stanford University in Palo Alto, California, who was also not involved in the study, made the point that “obesity affects every single body part and if you are able to affect the weight, you’re going to help other medical problems — particularly the ones that are inflammatory-mediated.”

“Obesity is really an inflammatory-mediated disease, and stroke, cardiac risk, and even diabetes are now being recognized as inflammatory-related. With weight-loss surgery, direct markers of inflammation go down and, more importantly, these diseases get better,” Dr. Morton explained.

Studies have shown that morbidly obese patients can lose 30% to 50% of their excess weight in the first 6 months after surgery, and 77% as early as 1 year after surgery.

American Society for Metabolic and Bariatric Surgery (ASMBS) 28th Annual Meeting. Abstract PL-105. Presented June 15, 2011.

Advertisements

Read Full Post »

Intra – Operative Myocardial Infarction 

One of the most feared, yet preventable complications is intra-operative / post operative myocardial infarction (heart attack).  Alarmingly, a new paper published on Medscape by Reed Miller suggests that too often we aren’t doing enough to prevent this devastating complication and miss the diagnosis of this condition when it does occur*.

In many cases, patients are asymptomatic, which is no cause for relief – since the thirty day mortality after post-operative infarction is frightening high.  Part of my job in my practice as an acute care nurse practitioner in cardiovascular and thoracic surgery is to perform pre-operative risk stratification and risk reduction for this, and other potentially preventable complications.

There are several important, but easy things we can do to reduce the risk of our patients having a heart attack during or immediately after surgery:

Pre-operative Evaluation:

1. First, screen your patient for the presence of anginal symptoms and associated risk factors – before scheduling an operation.  Surprisingly, many patients are experiencing atypical angina, dyspnea on exertion and other symptoms in their daily lives, yet ascribe these symptoms to “being out-of-shape” or “getting old”.

If there is one thing, I’ve learned after greeting people in the cardiac cath lab to tell them they need heart surgery – it’s that the majority of people tend to ignore or overlook subtle signs until acute chest pain, or an infarction brings them to the hospital.  So, ask you patients about these symptoms, so you aren’t surprised in the operating room.

Ask yourself, What other risk factors do they have?

–     Diabetes, (of any duration) should prompt consideration for pre-operative cardiology workup and a possible exercise stress test.

–     Claudication (peripheral vascular disease), carotid stenosis (or hx of TIAs) or any other history suggestive of arterial disease

–     Elevated cholesterol or unknown cholesterol status, history of cholescystetomy or gallbladder disease or visible xanthomas (particularly on the face)

–    Advanced age – anyone over the age of 65

–    Hypertension, particularly if poorly controlled

–    Anemia, of any origin

–    Poor overall health, poor exercise tolerance (again this may be related to undiagnosed angina)

2. Secondly, Pre-operative Maximization!! This is important for  all major surgeries, but often isn’t implemented for orthopedic, general surgery and other large surgeries.  The other thing to realize is, this isn’t the anesthesia team’s job; it’s the attending surgeon and the primary care physician (jointly).  This means controlled, or correcting all of the items listed  in the previous section (as much as possible):

– cardiac evaluation for patients at medium / high risk for cardiac disease – and having an index of suspicion for people with vague  symptoms.

– treating underlying disease conditions – for example, if your patient has a hemoglobin A1c of 9.0 – delay elective cases until glucose is better managed.  Remember to monitor and manage glucose in the operating room too – unfortunately, this is often only done in cardiac surgery, but it’s important during all surgeries.  Intraoperative Hyperglycemia is an independent risk factor for myocardial infarction/ and is considered a ‘marker’ for infarction.

And check everyone, not just diagnosed diabetics – since hyperglycemia occurs in some normal individuals under physiological stress, and diabetes is grossly underdiagnosed.

Don’t discontinue statins pre-operatively – not only does evidence suggest that statins are protective against intraoperative strokes and sepsis, but the evidence to support discontinuing these medications preoperatively is slim.  Too often, we
discontinue patients needed medications as part of a routine, not an individualized treatment plan.  (Now clopidogrel (Plavix) and warfarin are a little different, but sometimes we continue these medications too – in very
select cases..)

Pre-operative beta blockade – the evidence is overwhelming
in favor of pre-operative beta blockade, yet some people are still neglecting
this (or even stopping these medications in people already on them.)  Continue metoprolol, carvedilol, propanolol, and make sure to ask why patients are taking them in the first place.  “Heart medicine” is an answer that should prompt further investigation.

– Consider and re-consider before discontinuing Aspirin.  In our thoracic (and cardiac ) surgery patients – we always continue aspirin, safely, and have had no increase in bleeding complications.  Often, surgeons can very safely operate on patients taking aspirin – but discontinuing it in these patients may contribute to the risk of intraoperative/ postoperative infarction.

Intraoperatively:

–  Control that heart rate!  We KNOW through decades of research that
slower is better.  Keep the heart rate at sixty or below to reduce cardiac demand.

–   Prevent hypotension – keep the MAP at 70 or above (and be particularly intolerant of hypotension in anyone with a cardiac history –you don’t want to collapse those grafts.
Remember that patients with vasculopathic disease don’t tolerate low
blood pressure as well as you or I – and don’t allow it (low blood pressure) to happen.

–    Monitor for changes in telemetry during the case.

–    Monitor and control hyperglycemia (as mentioned above.)

Article Re-Post from Medscape (Reed Miller):

MIs After Noncardiac Surgery are Often Overlooked

April 20, 2011 (Hamilton, Ontario) — A new study from the Perioperative Ischemic Evaluation (POISE) trial suggests that monitoring non–cardiac-surgery patients for asymptomatic MIs in the first few days after surgery could dramatically reduce their short-term mortality risk [1].

The study shows that “consistently, all over the world, people are at substantial risk of suffering a heart attack after surgery, and if they do, they’re at substantial risk to die or suffer a major event in the coming days, and we need to do a better job to detect them and manage them,” primary author Dr PJ Devereaux (McMaster University, Hamilton, ON) told heartwire. “We want to make the broader cardiology world aware that this is a huge emerging epidemic that’s going to confront cardiology, because there are 200 million adults having surgery every year in the world. . . . We need to get a lot more aggressive about monitoring for these events and recognizing that the majority of people won’t have symptoms when they have these events.”

Devereaux and colleagues followed 8351 patients at 190 centers in 23 countries with four cardiac biomarker assays for three days postsurgery. All of the patients were part of the original POISE trial, reported by heartwire, which showed that beta blockers reduce the risk of MI but increase the risk of severe stroke and overall death in patients undergoing non–cardiac surgery (including orthopedic, cancer, and noncardiac vascular surgeries). Results of the new study by Devereaux et al are published in the April 19, 2011 issue of the Annals of Internal Medicine.

“Surgery is sort of the ultimate stress test. It does everything that is relevant to causing acute coronary syndrome. It’s very proinflammatory, and it activates the sympathetic system, coagulation, and platelets. That’s why we have this problem of people having myocardial infarction after surgery, [and yet until now] there’s not that much research on the outcomes of heart attacks after surgery,” Devereaux told heartwire. Patients and physicians are often unaware of an MI during this early postoperative period because most of the patients are on high doses of narcotics that “blunt the discomfort of the surgery but may mask ischemic symptoms,” Devereaux said.

Within 30 days of randomization, 415 patients in the study (5.0%) showed evidence of a perioperative MI, defined as either autopsy findings of acute MI or an elevated level of a cardiac biomarker or enzyme assay plus ischemic symptoms, development of pathologic Q waves, ischemic changes on electrocardiography, coronary artery intervention, or cardiac imaging evidence of MI. Nearly three-quarters of the MIs happened within 48 hours of the surgery, but almost two-thirds of the MI patients did not did not experience ischemic symptoms. In fact, patients with a periprocedural MI without ischemic symptoms had a higher mortality rate (12.5%) than those who had symptoms (9.7%).

The short-term prognosis for patients who suffer periprocedural MIs is very poor, with 11.6% mortality at 30 days postprocedure compared with 2.2% for patients who did not suffer a periprocedural MI (p<0.001). Furthermore, Devereaux noted that a recent meta-analysis by his group found that people who suffer a periprocedural MI continue to be at higher risk for death than those who do not for at least a year after the surgery.

Nobody thinks twice about being incredibly assertive about managing an MI in the emergency room . . . [and yet] those MIs have a much better prognosis than these MIs, and we’re ignoring these MIs for the most part.

Regression analysis of the data showed that relatively simple therapies could have prevented many of these deaths. In the study, patients on aspirin had about half the 30-day mortality risk as those not on aspirin, while statins reduced the 30-day mortality rate by about three-quarters. Only 64.8% of patients who suffered an MI in the trial were on aspirin, only 17.8% were receiving clopidogrel or ticlopidine, 52.0% were receiving a statin, and 55.4% were receiving an ACE inhibitor or angiotensin-receptor blocker.

“Patients expect us to look for things that are modifiable and change their risks of very serious events quickly, and perioperative MI is definitely in that category,” Devereaux said. “Nobody thinks twice about being incredibly assertive about managing an MI in the emergency room, which is completely appropriate, but those MIs have a much better prognosis than these MIs, and we’re ignoring these MIs for the most part.”

Commenting on the study by Devereaux et al, Dr Adrian Banning (John Radcliffe Hospital, Oxford, UK) told heartwire, “We are not optimizing medical therapy before surgery. There are existing guidelines and risk scores that are probably underused. Preoperative testing for ischemia and revascularization is probably overused in a minority of patients, leaving an occult majority without simple medical measures that are likely to be beneficial–including aspirin, statins, and good perioperative blood-pressure control.”

More Research Needed to Clarify Who Is at Risk and How to Treat Them

Devereux’s group is currently enrolling patients into the 40 000-patient prospective cohort VISION study, which is intended to define the optimal approach for predicting major perioperative vascular events, the extent to which troponin measurement after surgery can identify asymptomatic MIs, and these patients’ risk of vascular-related death within one year.

The first 20 000 patients in the study have been monitored with “fourth-generation” troponin assays, and the next 20 000 will be monitored with higher-sensitivity troponin assays. Commenting on the research, Dr Stephen Ellis (Cleveland Clinic, OH) pointed out that with the advent of highly sensitive troponin tests, more research will be needed to define what degree of troponin change is clinically important. “I’m sure there’s some level of troponin where you see a bump that doesn’t mean anything.” For example, Banning and colleagues recently completed a study that suggests the current standard troponin cutoff used to detect an MI has been arbitrarily set too low and leads to an overestimate of the number of MIs.

Dr John French (University of New South Wales, Australia) added that future research should also try to risk-stratify these patients by collecting both pre- and postprocedural troponin levels. Elevated preprocedural troponin may also be a risk marker, he told heartwire.

Devereaux hopes there will also soon be a large national trial to evaluate the best way to manage non–cardiac-surgery patients in the vulnerable perioperative period. Ellis agreed that “we don’t really understand the benefits of some of the medical treatments that we have in our armamentarium in this patient population. . . . There may be some other treatments that are less utilized at present that could cut down on the incidence of perioperative infarction.”

Banning agreed that further research is needed to understand how to prevent these perioperative MIs, not merely detect them. “Troponin measurement postoperatively can help define a risk group with adverse outcome, [but] it is uncertain that we can influence that adverse outcome once the event has happened in those patients already on optimal medical therapy,” he said. “There will be a group identified by routine troponin testing where this event is the first declaration of occult coronary disease, and perhaps this group potentially has the most to gain.”

Although the best approach to managing these patients has yet to be clearly defined, Devereaux emphasized that “in the short term, there’s a lot of intuitive things that we can do better that will likely improve the outcomes, and there’s lots of reasons to be optimistic that, even if we just start monitoring them, we can improve the outcomes.” Devereaux recommends that physicians caring for a surgery patient order a troponin test sometime between six and 12 hours after the surgery and then repeat tests for the first three days after surgery.

His institution has made perioperative MI prevention a priority for its cardiologists. “We’ve changed cardiology from regular cardiology to cardiology and perioperative vascular medicine,” he said. All surgery patients’ cardiac biomarkers are monitored, and the patients are triaged to the coronary care unit or less-intensive care based on their MI risk. He expects his group will be able to present data on the impact of this approach within the next year.

This study was supported by the Canadian Institutes of Health Research, the Commonwealth Government of Australia’s National Health and Medical Research Council, the Instituto de Salud Carlos III in Spain, the British Heart Foundation, and AstraZeneca.

part of patient education series – Ask your doctor about your risk for peri-operative MI, and what he’s doing to reduce your risk.

* Diagnosing MI after surgery is another article.

Read Full Post »