DEAR DR. ROACH: I am struggling with a decision process due to a lack of consensus among various physicians. I was fortunate back in January at 66 years of age to survive bilateral pulmonary emboli with syncope when my wife successfully performed CPR. The underlying cause is undetermined as multiple tests have been negative.

I’m now on blood thinners (Eliquis), and I have one cardiologist who says that this must be the case for the rest of my life, while another disagrees. I had a hematologist say that it is not worth determining the root cause because blood thinners are the outcome regardless. Yet my long-time cardiologist disagrees and plans to refer me to a different hematologist.

My reading suggests that long-term blood thinner use is not favorable. Recent blood work with my general physician was good, and he tends to lean toward finding out the root cause. Any suggestion on how to referee when there’s a lack of consensus from physicians?

• T.W.

ANSWER: In my opinion, the medical evidence is on the side of the first cardiologist and the hematologist. A single life-threatening blood clot event is a usual indication for lifelong anticoagulation when a reversible cause cannot be found. Yours was not merely life-threatening; it would have been life-ending if not for the heroic action of your wife.

The hematologist is also right that lifelong anticoagulation is the correct treatment even if a genetic cause could be identified. It is very unlikely that a reversible cause will be found after an initial diligent search. However, there still may be a reason to try to find the cause as it may bear on other members of your family, even if it doesn’t affect your treatment.

While it is true that there are risks to lifelong anticoagulation, especially bleeding, you may not be lucky enough to survive another blood clot in your lung. In my estimation, the benefit of anticoagulation greatly outweighs its risks.

DEAR DR. ROACH: I had a complete knee replacement. Now when I go to the dentist, he insists that I take a one-time dose of clindamycin (600 mg) on the day of the visit. (I am allergic to penicillin.) My orthopedist laughs and says that this is old-fashioned; he recommended that I don’t take it. Any advice?

• S.M.

ANSWER: Although I don’t advocate laughing at any of our fellow professionals, your orthopedic surgeon is correct that antibiotics prior to a routine dental visit is no longer recommended for people with orthopedic hardware.

ToYourGoodHealth@med.cornell.edu.