That's one helluva way to spend a birthday: the only people I spoke to in person last Wednesday were the cardiac nurse and the ultrasound tech. I talked to my Mom on the phone for a bit and traded messages with the girls, but that was it. Given how the morning started, that isolation was probably for the best.
Quick recap: I get really dizzy after hard workouts. I've blacked out on the bike twice this year, and my ability to hold watts at my lactic / functional threshold has been on the decline all summer. I experience shortness of breath at five beats a minute below threshold (165 beats per minute makes me feel like I'm breathing through a straw), and I have no power past zone 3 / ME / tempo. My blood pressure's low (good?) as are my cholesterol and resting heart rate. I feel fine except when I try to push myself on the bike and after I finish a ride.
An initial EKG indicated an early repolarization. Coupled with the syncope symptoms, that result spurred my internal medicine doctor to refer me to Creighton's Cardiac Center for a full-on stress test.
I know now that I look stupid with a bare chest--the cardiac nurse shaved off most of my chest hair to get a better seal under the sensors. She hooked me up to an EKG and a technician took ultrasound video of my heart at rest. Then they asked me to run on a treadmill while still connected to all the electrodes and the blood pressure cuff, a task much harder than it sounds. Based on my age ("Yes, nurse, it's my birthday. No, I have no other plans"), they were hoping to see 152 beats per minute. I told them that I usually suffered symptoms at around 161 or so, but they reminded me that my running and cycling threshold heart rates might be different.
The treadmill was narrow and short, and my right arm was wrenched backward by the blood pressure cuff and mass of wires running from the electrodes to the EKG. Plus, I just kinda run like a walrus. It was an awkward few minutes.
I jumped off the treadmill at 160 beats a minute and lay back down on the table for another ultrasound. The nurse said she saw nothing worrisome on the EKG, but the ultrasound tech left without comment as soon as he finished. I found that worrisome--he'd been relatively talkative earlier in the session.
I've called the doctor three times, but I can't get past his receptionist, who tells me the doctor will call when he gets the results. Crap.
I skipped riding on Wednesday, rode really easy on Thursday and Saturday, but utterly failed to finish a threshold effort with Bryan yesterday. I felt okay as we rolled out of town, but every time I tried to get my wattage above 300 -- or my heart rate higher than 165 -- I just fell apart. It feels like my lungs have shrunk, somehow.
So I wait. I'm skipping Wednesday Night Worlds again tonight and plan to ride easy tempo tomorrow and Saturday. If I haven't gotten some news from the doctors by Friday, I may pay the office an impromptu visit.
From wikipedia (yes, I know it's often crap):
Factors that influence fainting are fasting long hours, taking in too little food and fluids, low blood pressure, hypoglycemia, growth spurts, physical exercise in excess of the energy reserve of the body, emotional distress, and lack of sleep. Orthostatic hypotension caused by standing up too quickly or being in a very hot room can also cause fainting.
More serious causes of fainting include cardiac (heart-related) conditions such as an abnormal heart rhythm (an arrhythmia), wherein the heart beats too slowly, too rapidly, or too irregularly to pump enough blood to the brain. Some arrhythmias can be life-threatening. Other important cardio-vascular conditions that can be manifested by syncope include subclavian steal syndrome and aortic stenosis.
Orthostatic (postural) hypotensive faints are as common or perhaps even more common than vasovagal syncope. Orthostatic faints are most often associated with movement from lying or sitting to a standing position. Apparently healthy individuals may experience minor symptoms ("lightheadedness", "greying-out") as they stand up if blood pressure is slow to respond to the stress of upright posture. If the blood pressure is not adequately maintained during standing, faints may develop. However, the resulting "transient orthostatic hypotension" does not necessarily signal any serious underlying disease. The most susceptible individuals are elderly frail individuals, or persons who are dehydrated from hot environments or inadequate fluid intake.