Month: February 2020

Posted on

No Role of Prior Hydration in Prevention of Contrast Induced Nephropathy

The common practice of hydration with sodium bicarbonate prior to contrast-enhanced CT imaging shows no benefit in terms of renal safety compared to withholding hydration in patients with stage 3 chronic kidney disease (CKD), new research shows.

“To our knowledge, our study is the first that directly compares no prehydration with sodium bicarbonate prehydration prior to nonemergency contrast-enhanced CT with intravenous iodine-based contrast media administration,” the authors of the new Kompas trial report.

“Based on these results, we believe that our study provides sufficient evidence that preventive hydration can be withheld in this population.”

Although acute kidney injury (AKI) following the administration of iodine-based contrast media with CT imaging is known to generally be mild and without long-term effects, international guidelines still call for preventive hydration, with sodium bicarbonate or isotonic saline, for high-risk patients.

Few studies, however, have evaluated the efficacy and safety of hydration prophylaxis compared with no hydration.

No Difference in Outcomes, Fewer Costs, With No Prehydration

For the multicenter Kompas trial, published online February 17 in JAMA Internal Medicine, Rohit J. Timal, MD, and colleagues enrolled 523 patients with stage 3 CKD at six hospitals in the Netherlands.

Patients were randomized 1:1 to receive prehydration with 250 mL of 1.4% sodium bicarbonate or no hydration prior to undergoing elective contrast-enhanced CT between April 2013 and September 2016.

Patients were a median age of 74 and 64.2% were male.

For the primary endpoint of mean relative increase in serum creatinine level 2-5 days following contrast administration, the mean increase in the prehydration group, compared with baseline, was 3.5% (SD, 10.3) versus 3.0% (SD, 10.5) in the no prehydration group (mean difference, 0.5%; 95% CI, −1.3 to 2.3; P < .001 for noninferiority).

Furthermore, there were no significant differences in the secondary outcomes of post-contrast AKI, which occurred in 1.5% (4 of 261) of patients in the prehydration group and 2.7% (7 of 262) of the no prehydration group (P = .36).

The predefined subgroup analysis also showed no significant differences.

There were no reports of acute heart failure, and none of the patients required dialysis.

Importantly, the withholding of hydration also reduced costs, with hydration costing on average $144 per patient, compared with no cost if prophylaxis was withheld, note Timal, of the Department of Cardiology, Leiden University Medical Center, the Netherlands, and coauthors.

“Omission of prophylactic measures did not lead to increased healthcare expenses during the 2 months’ follow-up,” they write.

There are some notable limitations, including the fact that because serum creatinine level was assessed only in patients with CKD undergoing elective CT, the results cannot be extrapolated to angiography with intra-arterial contrast administration or to acute interventions, such as percutaneous transluminal (coronary) interventions.

In addition, for feasibility reasons, the study was powered for a relative increase in serum creatinine level instead of post-contrast AKI, consistent with other studies, the authors note.

“This is a consequence of the noninferiority design and the low risk of post-contrast-AKI in this clinical setting,” they explain.

In conclusion, Timal and colleagues write: “Among patients with stage 3 CKD undergoing contrast-enhanced CT, withholding prehydration did not compromise patient safety. The findings of this study support the option of not giving prehydration as a safe and cost-efficient measure.”

Source : Medscape

Posted on

Invasive Revascularizations Halved , PCI’s More Than Doubled

Over the 13-year period ending in 2016, revascularization procedural volumes have dropped by half, although the percentage of percutaneous coronary intervention (PCI) procedures done for myocardial infarction (MI) have more than doubled, a new administrative study shows.

During the same period, risk-adjusted in-hospital mortality rates after coronary artery bypass grafting (CABG) have also improved, whereas in PCI for ST-segment elevation myocardial infarction (STEMI), they’ve hovered stubbornly around 5%.

“I actually started this study because I wanted to see whether STEMI patients who get PCI are doing better over time, and what we found was that, while the CABG cohort saw a substantial reduction in mortality by almost half, with PCI, in-hospital mortality remained about 5% over time and didn’t change,” said Mohamed Alkhouli, MD, the Mayo Clinic, Rochester, Minnesota.

To better understand temporal trends and outcomes of patients undergoing coronary revascularization in the United States, the researchers analyzed retrospective data from the Nationwide Inpatient Sample (NIS) database covering patients undergoing PCI or CABG from January 1, 2003 to December 31, 2016.

NIS sampling covers more than 97% of the American population, making this the largest and longest report on revascularization trends in the United States in recent years.

Researchers reported the findings of their study online February 14 in JAMA Network Open.

A total of 12,062,081 revascularization hospitalizations were identified: about 8.69 million (72.0%) PCIs and 3.37 million CABGs.

Risk-adjusted in-hospital mortality after PCI increased modestly between 2003 and 2016 for patients with STEMI, from 4.9% to 5.3% (P < .001 for trend), but mostly remained stable after PCI for non-STEMI (1.6% for both periods; P = .18) or unstable angina-stable ischemic heart disease (SIHD, 0.8% to 1.0%; P < .001).

In the CABG cohort, risk-adjusted in-hospital mortality decreased significantly from 2003 to 2016, from 5.6% to 3.4% (P < .001 for trend) for patients undergoing CABG in the context of AMI.

“Part of it could be that we are doing PCI in more complex patients [and the risk adjustment isn’t sufficient], but it’s still something that needs to be better understood and should be food for thought to better understand why we haven’t been able to improve outcomes in those individuals,” said editorial writer Debabrata Mukherjee, MD, Texas Tech University, El Paso.

PCI and CABG Volumes Down

The COURAGE trial was first presented in 2007 and showed that, for patients with SIHD, revascularization did not improve outcomes over optimal medical therapy. Based on the findings of this current study, it appears that message was heard loud and clear.

PCI volume decreased from 777,780 in 2003 to 440,505 in 2016, or from 366 to 180 per 100,000 American adults, a “dramatic decrease of about half, indexed to the population,” said Alkhouli in an interview.

However, the percentage of PCIs done for MI more than doubled, from 22.8% in 2003 to 53.1% in 2016.

“I think it’s a result of the recognition that stable patients are likely to be okay managed medically based on the COURAGE trial and other trials. The ISCHEMIA [trial] may even support a further decrease in the future and I think it will be interesting to repeat the same study in another 5 years,” said Alkhouli.

Alkhouli noted that many catheterization laboratories may not be suffering from these drops in volume because of the concurrent uptick in other endovascular procedures.

“I think [the decrease] wasn’t dramatically visible because of the increase in peripheral interventions and structural heart disease procedures over the years,” he said. “So, the cath lab is still doing ten cases a day, or whatever, but the mix of cases has changed.” He noted that other smaller studies corroborate this decrease in PCI.

Similarly, annual CABG volumes decreased from 159 to 82 per 100,000 American adults, but CABG for MI increased from 19.5% to 28.2%.

Both Alkhouli and Mukherjee told theheart.org | Medscape Cardiology that they see this drop in procedures as a real win.

“I’d give the American College of Cardiology credit for coming out with appropriateness criteria to make sure that people are appropriately using things like fractional flow reserve to make sure that we are treating lesions that are truly hemodynamically significant,” said Mukherjee.

He suggested that with better use of primary and secondary preventive therapies — including newer and more potent antiplatelet and antithrombic agents, PCSK9 inhibitors, and ω3 fatty acids — down the line “revascularization may be rarely indicated in those with SIHD.

Source : Medscape

Posted on

GI Bleeding on Oral Anticoagulants in Atrial Fib Foremost a Colon Cancer Red Flag

Bleeding from the lower gastrointestinal (GI) tract shouldn’t be seen as simply a manageable adverse effect of oral anticoagulation (OAC) for atrial fibrillation (AF). Rather, it’s a red flag that the patient may be facing a much bigger threat, say researchers based on their observational study.

The absolute risk for lower-GI bleeding in a large national cohort of patients with AF who started on OAC was less than 1% over 6 months, regardless of age, and substantially less than 1% in patients 65 years and younger.

But those few with such bleeding showed a 10- to 15-fold increased 1-year risk for a diagnosis of colorectal cancer if they were older than 65, and 24 times that risk if they were 65 or younger, compared with those without lower-GI bleeding on OAC.

“Patients should be informed when initiating treatment with anticoagulants that blood in the stool should always lead to consulting their treating physician, and not be ignored as merely a benign consequence of treatment,” Peter Vibe Rasmussen, MD, University of Copenhagen, Hellerup, Denmark, told theheart.org | Medscape Cardiology.

“Our study included patients with bleeding severe enough for hospital contact. However, we think our data support that all eligible patients presenting with a sign or symptom of lower GI bleeding should be offered examinations to rule out cancer,” he said.

Only 61% of the youngest and less than 40% of the oldest patients with lower GI bleeds underwent endoscopy to investigate the cause, which points to “a potential underutilization of diagnostic procedures” in the cohort, said Rasmussen, who is lead author on the analysis, published February 7 in the European Heart Journal.

“I think we’re learning that we cannot just let those bleeds go without further investigation,” agreed Renato D. Lopes, MD, PhD, Duke Clinical Research Institute, Durham, North Carolina, speaking with theheart.org | Medscape Cardiology.

“Anticoagulants don’t make people bleed. What they do is magnify small bleeds or increase the likelihood of people bleeding because of underlying disease, in this case, GI cancer.”

So the current analysis, which supports and strengthens cautions from previous research, “is a wake-up call for us to not let any kind of bleed in the GI tract go without a more detailed investigation for potential cancer,” said Lopes, who isn’t connected with the current study.

That’s especially so as the newer generation of direct oral anticoagulants (DOAC) largely replaces warfarin and other vitamin K antagonists (VKA) in patients with AF.

“DOACs are much better than warfarin across the board, but they have one pitfall,” Lopes said. “It’s not true for all DOACs, but in general as a class, they cause more GI bleeding than warfarin.”

And that means “maybe we need to switch our mindset to be a bit more aggressive in the investigation of GI bleeds than we were in the warfarin era.”

Rasmussen said the study wasn’t sufficiently powered to compare DOACs and VKA for their effects on GI bleeding. The analysis is based on 125,418 patients in Danish administrative registries who initiated OAC for AF from 1996 through 2014, a time when such patients overwhelmingly received VKA. However, results were similar in a secondary analysis limited to only VKA recipients.

In the main analysis, the absolute risk for colorectal cancer in patients with vs without lower GI bleeding more than doubled from the 65-and-younger group to its peak in the 76-to-80-year age group. Meanwhile, the relative risk was highest in the youngest patients, who are likely to have fewer noncancer competing causes of GI bleeding than older groups.

It’s unknown whether a colorectal cancer diagnosis after investigation of an OAC-related bleed might often catch a malignancy at an earlier stage than otherwise would have occurred, “potentially increasing the likelihood of successful treatment,” Rasmussen said.

That’s possible, but “it should be seen in the perspective that any major bleeding is potentially harmful and could pose an immediate serious risk to the patient.”

Lower GI bleeding could indeed “trigger investigation of a more severe clinical disease, such as a cancer, and help save lives,” Lopes agreed. “Is that really impacting with lower mortality or less cancer related death? We don’t have that data yet.”

Source : Medscape

Posted on

First Robotic Supermicrosurgery For Lymphedema

The first trial of robot-assisted, high-precision supermicrosurgery in humans has shown that the technique is safe for treating breast cancer–related lymphedema.

Although results are preliminary — only 20 patients participated, and a single highly skilled surgeon performed the supermicrosurgery — additional trials are underway to test the new robotic technique at other centers.

The pilot study was published online February 11 in Nature Communications.

The new device, known as MUSA, was supplied by MicroSure.

MUSA allows surgeons to connect tiny vessels, as small as 0.3–0.8 mm across, a technique referred to as supermicrosurgery. This technique can be used to connect blocked lymph vessels to veins, which can reestablish flow of lymphatic fluid and decrease arm swelling in women with breast cancer–related lymphedema, the researchers explain.

Only a few highly skilled surgeons worldwide can conduct supermicrosurgery using current surgical techniques, the authors comment.

“The success of supermicrosurgery is limited by the precision and stability of the surgeon’s hands. Robot-assisted supermicrosurgery has the potential to overcome this obstacle because more refined and subtle movements can be performed. Before now, no robots were able to perform this type of surgery,” coauthor Rutger M. Schols, MD, PhD, from the Maastricht University Medical Center in the Netherlands, told Medscape Medical News in an email.

Robot-assisted surgery is not new — the Da Vinci system was the first robotic surgery device to be approved by the US Food and Drug Administration. It was approved in 2000. However, Da Vinci was developed for minimally invasive surgery and is not precise enough for supermicrosurgery. And despite its $2 million price tag, Da Vinci has yet to show that it performs better than traditional surgery.

Designed Specifically for Supermicrosurgery

The MUSA robot was designed in the Netherlands by surgeons at Maastricht University Medical Center, engineers at the Eindhoven University of Technology, and the medical technology company Microsure specifically for reconstructive supermicrosurgery. Two of the authors of the article hold positions and are shareholders in the company.

Surgeons activate MUSA using foot pedals and operate forceps-like joysticks to control high-precision surgical instruments that filter out hand tremors and scale down motions. For example, moving the joystick 1 cm causes the robot to move 0.10 mm. MUSA also works with standard microscopes found in most operating rooms.

To test MUSA, Schols and colleagues at Maastricht University conducted a prospective, randomized trial that included 20 women with breast cancer–related lymphedema. The team randomly assigned eight women to undergo supermicrosurgery with MUSA and 12 women to undergo manual supermicrosurgery performed by a single surgeon. Two microsurgeons who were blinded to treatment groups evaluated the quality of the surgery using standardized scoring methods.

The results, which were adjusted for baseline factors, showed no significant differences in upper limb lymphedema between the two groups 1 and 3 months after surgery, nor were there significant differences between the two groups in quality of life.

A slightly higher percentage of women in the MUSA group were able to discontinue daily use of a compressive garment to treat arm swelling at 3 months, compared to the group that underwent manual supermicrosurgery (87.5% vs 83.3%).

Participants reported no serious adverse events.

For the group that underwent manual surgery, the quality of anastomosis was significantly better, compared to the MUSA group. Surgical competency was also significantly higher in the group that underwent manual surgery.

The MUSA group experienced a longer total surgery time (mean, 115 min) compared to the group that underwent manual surgery (mean, 81 min). But the authors note that duration of surgery declined steeply over time for the MUSA group, suggesting a learning curve in using the robot.

The researchers caution that the study may have been too small to detect significant differences between groups. Larger studies are needed to test MUSA with other surgeons operating in other centers, the authors note.

“With respect to treatment of breast cancer–related lymphedema, we are continuing trials with more patients, more surgeons, and more centers,” Schols told Medscape Medical News.

“We expect that other centers — both national and international — are willing to test the MUSA,” he added

Source : Medscape